Polyrate 17-C Manual · 2021. 7. 17. · Polyrate 2 Executive summary: Polyrate 17-C is a suite of...

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Polyrate 1 Polyrate 17-C Manual Jingjing Zheng, Junwei Lucas Bao, Rubén Meana-Pañeda, Shuxia Zhang, Benjamin J. Lynch, José C. Corchado, Yao-Yuan Chuang, Patton L. Fast, Wei-Ping Hu, Yi-Ping Liu, Gillian C. Lynch, Kiet A. Nguyen, Charles F. Jackels, Antonio Fernandez Ramos, Benjamin A. Ellingson, Vasilios S. Melissas, Jordi Villà , Ivan Rossi, Elena. L. Coitiño, Jingzhi Pu, Titus V. Albu Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455 Artur Ratkiewicz Institute of Chemistry, University of Bialystok, Poland Rozeanne Steckler Northwest Alliance for Computational Science & Engineering, Oregon State University, Corvallis, Oregon 97331 Bruce C. Garrett Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352 Alan D. Isaacson Department of Chemistry and Biochemistry,Miami University, Oxford, Ohio 45056 and Donald G. Truhlar Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455 Most recent changes to program: June 16, 2018 for the part excluding the SS-QRRK utility; Dec. 22, 2018 for SS-QRRK utility. Most recent update to manual: July 17, 2021 Polyrate 17-C is available from the Truhlar Research Group Software site at https://comp.chem.umn.edu/polyrate/ Polyrate 17-C is being submitted to the Computer Physics Communications Program Library, and after acceptance it will also be available from the CPC Program Library at https://data.mendeley.com/journal/00104655? The code is made available free of charge. Licensing: The Polyrate 17-C code is licensed under the Apache-2.0 license. The Polyrate 17-C manual is licensed under the CC-BY-4.0 license.

Transcript of Polyrate 17-C Manual · 2021. 7. 17. · Polyrate 2 Executive summary: Polyrate 17-C is a suite of...

Page 1: Polyrate 17-C Manual · 2021. 7. 17. · Polyrate 2 Executive summary: Polyrate 17-C is a suite of computer programs for the calculation of chemical reaction rates of polyatomic species

Polyrate 1

Polyrate 17-C Manual

Jingjing Zheng, Junwei Lucas Bao, Rubén Meana-Pañeda, Shuxia Zhang,

Benjamin J. Lynch, José C. Corchado, Yao-Yuan Chuang, Patton L. Fast, Wei-Ping Hu, Yi-Ping Liu, Gillian C. Lynch, Kiet A. Nguyen, Charles F. Jackels,

Antonio Fernandez Ramos, Benjamin A. Ellingson, Vasilios S. Melissas, Jordi Villà, Ivan Rossi, Elena. L. Coitiño, Jingzhi Pu, Titus V. Albu

Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455

Artur Ratkiewicz

Institute of Chemistry, University of Bialystok, Poland

Rozeanne Steckler

Northwest Alliance for Computational Science & Engineering,

Oregon State University, Corvallis, Oregon 97331

Bruce C. Garrett

Environmental Molecular Sciences Laboratory,

Pacific Northwest National Laboratory, Richland, Washington 99352

Alan D. Isaacson

Department of Chemistry and Biochemistry,Miami University, Oxford, Ohio 45056

and Donald G. Truhlar

Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455

Most recent changes to program:

June 16, 2018 for the part excluding the SS-QRRK utility;

Dec. 22, 2018 for SS-QRRK utility.

Most recent update to manual: July 17, 2021

Polyrate 17-C is available from the Truhlar Research Group Software site at

https://comp.chem.umn.edu/polyrate/

Polyrate 17-C is being submitted to the Computer Physics Communications Program

Library, and after acceptance it will also be available from the CPC Program Library at

https://data.mendeley.com/journal/00104655?

The code is made available free of charge.

Licensing:

The Polyrate 17-C code is licensed under the Apache-2.0 license.

The Polyrate 17-C manual is licensed under the CC-BY-4.0 license.

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Polyrate 2

Executive summary:

Polyrate 17-C is a suite of computer programs for the calculation of chemical

reaction rates of polyatomic species (including atoms and diatoms as special cases) by

variational transition state theory (VTST); conventional transition state theory is also

supported. Polyrate 17-C (called Polyrate for short) consists of the main program,

called Polyrate, and a set of utility codes,

Polyrate can calculate the rate constants for both bimolecular reactions and

unimolecular reactions, and it can be applied to reactions in the gas-phase, liquid-solution

phase, or solid-state and to gas-solid-interface reactions. Polyrate can perform variational

transition state theory (VTST) calculations on gas-phase reactions with both tight and

loose transition states. For tight transition states it uses the reaction-path (RP)

variational transition state theory developed by Garrett and Truhlar, and for loose

transition states it uses variable-reaction-coordinate (VRC) variational transition state

theory developed by Georgievskii and Klippenstein.

The RP methods used for tight transition states are conventional transition state

theory, canonical variational transition state theory (CVT), and microcanonical

variational transition state theory ( VT) with multidimensional semiclassical

approximations for tunneling and nonclassical reflection. The tunneling approximations

available are zero-curvature tunneling (ZCT), small-curvature tunneling (SSCT), large-

curvature- tunneling (LCT), and optimized multidimensional tunneling (OMT). The SCT

option is the centrifugal dominant semiclassical adiabatic ground-state tunneling, and the

LCT options include both LC3 and LC4 including tunneling into excited states. One may

also treat specific vibrational states of selected modes with translational, rotational, and

other vibrational modes treated thermally.

For RP calculations, several options are available for reaction paths, vibrations

transverse to the reaction path, and transition state dividing surfaces. Generalized-

transition-state dividing surfaces may be defined on the basis of gradient directions in

isoinertial coordinates or by the re-orientation of the dividing surface algorithm. Reaction

paths may be calculated by the Euler steepest-descent, Euler stabilization, Page-McIver,

or variational-reaction-path algorithms. Vibrations away from the reaction path may be

defined by rectilinear (not recommended), nonredundant curvilinear, or redundant

curvilinear coordinates. Vibrational frequencies may be unscaled (not recommended) or

scaled.

For VRC calculations, rate constants may be calculated for canonical or

microcanonical ensembles or energy-and-total-angular-momentum resolved

microcanonical ensembles. VRC calculations are most appropriate for barrierless

association reactions. Both single-faceted and multifaceted dividing surfaces are

supported.

Pressure-dependent rate constants for elementary reactions can be computed using

system-specific quantum RRK theory (SS-QRRK) with the information obtained from

high-pressure-limit VTST calculation as input by using the SS-QRRK utility code. The

SS-QRRK utility program is part of the Polyrate distribution, and its usage is described in

a separate manual.

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Potential energy surfaces may be analytic functions evaluated by subroutines, or

they may be implicit surfaces defined by electronic structure input files or interface

subroutines containing energies, gradients, and force constants (Hessians). The use of

electronic structure calculations to calculate rate constants or other dynamical quantities

without an analytic potential energy surface is called direct dynamics.

Analytic surfaces may be used for variational transition state theory and any of the

types of tunneling calculations, single-level and dual-level calculations based solely on

electronic structure input files may be used for variational transition state theory and

zero-curvature or small-curvature tunneling, and dual-level calculations based on using

an analytic potential energy surface as the lower level and using an electronic structure

input file as the higher level may be used for variational transition state theory and any of

the types of tunneling calculations.

Polyrate supports six options for direct dynamics, namely (i) straight single-level

direct dynamics, (ii) zero-order interpolated variational transition state theory (IVTST-0),

(iii) first-order interpolated variational transition state theory (IVTST-1), (iv) interpolated

variational transition state theory by mapping (IVTST-M), (v) variational transition state

theory with interpolated single-point energies (VTST-ISPE), and (vi) variational

transition state theory with interpolated optimized corrections (VTST-IOC). VTST-IOC

and VTST-ISPE are examples of dual-level direct dynamics; and VTST-IOC is also

called triple-slash dynamics (///), where the triple slash denotes higher-order corrections

of the geometries at which energetic and Hessian corrections are calculated. Dual-level

methods may be applied with electronic structure data for both levels (dual-level direct

dynamics), or it may be applied with an analytical potential energy surface for the lower

level and electronic structure data for the higher level. When dual-level methods are

employed with electronic structure data for both levels, the lower level may be either

straight direct dynamics or IVTST-M.

This version of Polyrate contains 112 test runs, and 46 of these are for direct

dynamics calculations; 85 of the test runs are single-level runs, and 27 are dual-level

calculations.

Polyrate is designed to be used in conjunction with interfaces to electronic

structure programs for direct dynamics. Currently the following interfaces are available

(note that some of the interfaces were created with older versions of Polyrate, but they

should work with Polyrate as well):

Electronic structure package Interface

CHARMM with CHARMMRATE CRATE

GAMESS (or with GAMESSPLUS) GAMESSPLUSRATE

GAUSSIAN 16/GAUSSIAN 09 GAUSSRATE

JAGUAR JAGUARATE

MC-TINKER MC-TINKERATE

MORATE MOPAC

MULTILEVEL MULTILEVELRATE

NWCHEM NWCHEMRATE

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CONTENTS

TITLE PAGE AND EXECUTIVE SUMMARY ................................................................1

CONTENTS ......................................................................................................................... 4

PART I GENERAL INFORMATION ................................................................................ 12

1. INTRODUCTION..........................................................................................................12

2. RECOMMENDED CITATION FOR POLYRATE 17-C ..............................................................23

3. RECOMMENDED CITATIONS FOR INCORPORATED CODE ..........................................23

4. LICENSING ...................................................................................................................24

5. PROGRAM AND MANUAL DESCRIPTION .............................................................25

5.A. Code description, portability, and special files ......................................................25

5.B. Description of the manual ......................................................................................25

5.B.1. Referencing conventions .................................................................................26

5.B.2. Key references .................................................................................................27

PART II THEORY BACKGROUND AND CALCULATION DETAILS ON RP-VTST .... 28

6. THEORETICAL BACKGROUND ON RP-VTST .........................................................28

6.A. Basic theory............................................................................................................28

6.B. Vibrations, Rotations, and Translations .................................................................31

6.C. Partition functions ..................................................................................................34

6.D. Tunneling methods .................................................................................................35

6.E. Reactant and product properties .............................................................................37

6.F. Saddle point properties ...........................................................................................39

6.G. Reaction path..........................................................................................................40

6.G.1. SADDLE option ..............................................................................................41

6.G.2. NOSADDLE option ........................................................................................44

6.H. Reaction-path curvature .........................................................................................44

6.I. Transmission coefficients ........................................................................................46

6.J. Reaction rates including tunneling ..........................................................................48

6.K. Imaginary-frequency modes transverse to the reaction path..................................50

6.L. Equilibrium constant calculation ............................................................................51

6.M. Omitting the product..............................................................................................51

6.N. Optimized multidimensional tunneling calculations..............................................52

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6.N.1. COMT method ................................................................................................52

6.N.2. µOMT method.................................................................................................52

6.O. Interpolated VTST and mapped interpolation........................................................52

6.O.1. IVTST-0 and IVTST-1....................................................................................53

6.O.2. Interpolated VTST by mapping (IVTST-M)...................................................54

6.O.3. The mapped interpolation (MI) algorithm with the hooks ..............................56

6.P. Interpolated optimized corrections (VTST-IOC), a form of dual-level VTST.......56

6.Q. Interpolated algorithm for large-curvature tunneling calculations.........................58

7. PROGRAM STRUCTURE ............................................................................................59

7.A. Overview of program flow .....................................................................................59

7.B. Determining the sign of s .......................................................................................65

7.C. Restart options ........................................................................................................66

8. CALCULATIONS USING THE HOOKS .....................................................................68

8.A. Methods for interpolating beyond SLM and SLP with the hooks.............................68

8.B. Zero of energy ........................................................................................................68

8.C. User-Supplied analytic potential energy surface ....................................................69

8.C.1. Interface ...........................................................................................................69

8.C.2. Utility routines.................................................................................................72

8.D. Calculations using an electronic structure program through hooks .......................75

9. CALCULATIONS BASED ON AN ELECTRONIC STRUCTURE INPUT FILE.......81

9.A. Relation of Polyrate input to electronic structure package output.........................83

9.B. Orientation of the molecule at generalized transition states...................................84

9.C. Methods for interpolation of electronic structure data with files fu30 and fu40....85

9.D. Methods for interpolation of electronic structure data with file fu31 ....................87

10. SELECTED DETAILS OF THE CALCULATIONS ..................................................88

10.A. Extrapolation of the reaction-path data beyond the range of the original grid ....88

10.B. Options for anharmonicity....................................................................................90

10.B.1. WKB anharmonicity based on a quadratic-quartic fit ...................................91

10.B.2. WKB anharmonicity based on the true potential ..........................................92

10.B.3. Hindered rotor treatments..............................................................................92

10.C. Alternate method for the calculation of numerical second derivatives ................98

10.D. Reaction-path following methods ........................................................................99

10.E. Interpolation of small-curvature effective reduced mass ...................................101

10.F. Reaction-path curvature calculation ...................................................................101

10.G. Solid-state and gas-solid interface reactions ......................................................102

10.H. VTST-IOC calculation, including ICR, ICL, and ICA schemes........................102

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10.I. VTST-ISPE calculation .......................................................................................106

10.J. Alternative methods for mapped interpolation ....................................................109

10.K. Quantized-reactant-state tunneling calculation ..................................................110

10.L. Curvilinear generalized normal mode analysis ..................................................110

10.M. IVTST0FREQ option ........................................................................................112

10.N. LCG4 option.......................................................................................................116

10.O. MS-VTST, MP-VTST, FMS-VTST, and FMR-VSTT calculations by using both

the Polyrate and MSTOR programs ...............................................................................118

PART III THEORY BACKGROUND FOR VRC-VTST.................................................. 125

11. THEORETICAL BACKGROUND ON VRC-VTST..................................................125

11.A. Variable reaction coordinate ..........................................................................125

11.B. Multifaceted dividing surface.........................................................................131

11.C. Overview of program flow for VRC-VTST calculation ................................132

11.D. Implementation details of the E, J-resolved microcanonical VRC algorithm 132

PART IV DESCRITION OF INPUT FILES..................................................................... 135

12. DESCRIPTION OF INPUT FOR RP-VTST ...............................................................135

12.A. General description of file fu5 input ..................................................................135

12.A.1. Section descriptions ....................................................................................137

12.A.2. GENERAL section ......................................................................................138

12.A.3. ENERGETICS section ................................................................................148

12.A.4. SECOND section ........................................................................................151

12.A.5. OPTIMIZATION section ............................................................................154

12.A.6. REACT1, REACT2, PROD1, PROD2, WELLR, WELLP, AND START

sections .....................................................................................................................161

12.A.7. PATH section ..............................................................................................181

12.A.8. TUNNEL section.........................................................................................213

12.A.9. RATE section ..............................................................................................224

12.B. General description of file fu29 input ................................................................236

12.B.1. E1GEOM Section ........................................................................................237

12.B.2. E1GRAD Section ........................................................................................237

12.B.3. E1HESS, P1HESS, P2HESS, R1HESS, R2HESS, and TSHESS sections .237

12.B.4. IVTST Section.............................................................................................238

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12.B.5. P1FREQ, P2FREQ, R1FREQ, R2FREQ, and TSFREQ sections ...............240

12.C. General description of file fu30 input ................................................................241

12.D. General description of file fu31 input ................................................................251

12.D.1. Section descriptions ....................................................................................251

12.D.2 GENERAL section .......................................................................................253

12.D.3. REACT1, REACT2, PROD1, PROD2, WELLR, WELLP, and SADDLE

sections .....................................................................................................................258

12.E. General description of file fu40 input.................................................................261

12.E.1 Section Descriptions .....................................................................................261

12.E.2 GEN40 section..............................................................................................262

12.E.3 R140, R240, P140, P240, WR40, and WP40 sections .................................269

12.E.4 SADDLE40 section ......................................................................................272

12.E.5 POINT40 section ..........................................................................................274

12.F. General description of unit fu50 input ................................................................279

12.G. General description of unit fu51 input ...............................................................291

12.G.1. Section Descriptions....................................................................................291

12.G.2 ISPEGEN section .........................................................................................292

12.G.3 POINT section..............................................................................................296

13. DESCRIPTION OF INPUT FOR VRC-VTST ............................................................298

13.A Section descriptions of input file fu5 ..................................................................298

13.A.1. GENERAL section ......................................................................................298

13.A.2. ENERGETICS section ................................................................................302

13.A.3. OPTIMIZATION section ............................................................................303

13.A.4. REACT1, REACT2, PROD1, AND START sections ................................304

13.A.5. PATH section ..............................................................................................307

13.A.6. RATE section ..............................................................................................308

14. GENERAL DESCRIPTION OF LCT FILES.............................................................309

PART V MORE GENERAL PROGRAM PACKAGE INFORMATION ......................... 310

15. INSTALLING AND USING POLYRATE .....................................................................310

15.A. Instructions for a Unix environment ..................................................................310

15.A.1. Installation ...................................................................................................310

15.A.2. Testing .........................................................................................................316

15.A.3. Using POLYRATE ..........................................................................................318

15.B. Comments for expert users .................................................................................321

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15.C. Running in parallel using MPI ...........................................................................322

16. SAMPLE TEST RUNS ..............................................................................................325

16.A. Chart of the potential energy functions and data files........................................325

16.B. Descriptions of sample test runs.........................................................................325

16.C.1. Test run ch5j1tr1 .........................................................................................329

16.C.2. Test run ch5j1tr2 .........................................................................................331

16.C.3. Test run ch5j1tr3 .........................................................................................332

16.C.4. Test run ch5j1tr4 .........................................................................................333

16.C.5. Test run ch5j1tr5 .........................................................................................334

16.C.6. Test run ch5j1tr6 .........................................................................................335

16.C.7. Test run ch5j1tr7 .........................................................................................336

16.C.8. Test run ch5j1tr8 .........................................................................................337

16.C.9. Test run ch5j1tr9 .........................................................................................338

16.C.10. Test run ch5j1tr10 .....................................................................................340

16.C.11. Test run ch5j1tr11 .....................................................................................341

16.C.12. Test run ch5j2tr1 .......................................................................................342

16.C.13. Test run ch5j1tr12 .....................................................................................343

16.C.15. Test run ch5j2tr3 .......................................................................................345

16.C.16. Test run ch5j2itr1 ......................................................................................346

16.C.17. Test run ch5j2itr2 ......................................................................................347

16.C.18. Test run ch5fu29tr1 ...................................................................................348

16.C.19. Test run ch5fu29tr2 ...................................................................................349

16.C.20. Test run ch5fu30tr1 ...................................................................................350

16.C.21. Test run ch5fu30tr2 ...................................................................................351

16.C.22. Test run ch5fu30tr3 ...................................................................................352

16.C.23. Test run ch5fu30tr4 ...................................................................................353

16.C.24. Test run ch5fu30tr5 ...................................................................................354

16.C.25. Test run ch5fu30tr6 ...................................................................................355

16.C.26. Test run ch5fu31tr1 ...................................................................................356

16.C.27. Test run ch5fu40tr1 ...................................................................................357

16.C.28. Test run ch5fu40tr2 ...................................................................................358

16.C.29. Test run ch5fu40tr3 ...................................................................................359

16.C.30. Test run ch5fu40tr4 ...................................................................................360

16.C.31. Test run ch5fu40tr5 ...................................................................................361

16.C.32. Test run ch5fu40tr6 ...................................................................................363

16.C.33. Test run ch5fu50tr1 ...................................................................................364

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16.C.34. Test run ch5fu50tr2 ...................................................................................365

16.C.35. Test run ch5fu50tr3 ...................................................................................366

16.C.36. Test run ch5fu51tr1 ...................................................................................367

16.C.37. Test run ch5icfu30tr1 ................................................................................368

16.C.38. Test run ch5icfu30tr2 ................................................................................369

16.C.39. Test run ch5icfu31tr1 ................................................................................370

16.C.40. Test run ch5icfu40tr1 ................................................................................371

16.C.41. Test run ch5icfu40tr2 ................................................................................372

16.C.42. Test run clhbrtr1 ........................................................................................373

16.C.43. Test run clhbrtr2 ........................................................................................375

16.C.44. Test run clhbrtr3 ........................................................................................376

16.C.45. Test run clhbrtr4 ........................................................................................377

16.C.46. Test run clhbr1tr5 ......................................................................................378

16.C.47. Test run cmctr1..........................................................................................379

16.C.48. Test run cmctr2..........................................................................................380

16.C.49. Test run cmctr3..........................................................................................381

16.C.50. Test run cwmctr1 .......................................................................................382

16.C.51. Test run cwmctr2 .......................................................................................383

16.C.52. Test run cwmctr3 .......................................................................................384

16.C.53. Test run h3tr1 ............................................................................................385

16.C.54. Test run h3tr2 ............................................................................................386

16.C.55. Test run h3tr3 ............................................................................................387

16.C.56. Test run h3tr4 ............................................................................................388

16.C.57. Test run ho2tr1 ..........................................................................................389

16.C.58. Test run ho2tr2 ..........................................................................................390

16.C.59. Test run ho2tr3 ..........................................................................................391

16.C.60. Test run ho2tr4 ..........................................................................................392

16.C.61. Test run ho2tr5 ..........................................................................................393

16.C.62. Test run nh3tr1 ..........................................................................................394

16.C.63. Test run nh3tr2 ..........................................................................................395

16.C.64. Test run oh3tr1 ..........................................................................................396

16.C.65. Test run oh3tr2 ..........................................................................................397

16.C.66. Test run oh3tr3 ..........................................................................................398

16.C.67. Test run oh3tr4 ..........................................................................................399

16.C.68. Test run oh3tr5 ..........................................................................................400

16.C.69. Test run oh3tr6 ..........................................................................................401

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16.C.70. Test run oh3tr7 ..........................................................................................402

16.C.71. Test run oh3tr8 ..........................................................................................403

16.C.72. Test run oh3tr9 ..........................................................................................404

16.C.73. Test run oh3tr10 ........................................................................................405

16.C.74. Test run oh3fu30tr1 ...................................................................................406

16.C.75. Test run oh3fu30tr2 ...................................................................................407

16.C.76. Test run oh3fu30tr3 ...................................................................................408

16.C.77. Test run oh3fu30tr4 ...................................................................................409

16.C.78. Test run oh3fu30tr5 ...................................................................................410

16.C.79. Test run oh3fu30tr6 ...................................................................................411

16.C.80. Test run oh3fu31tr1 ...................................................................................412

16.C.81. Test run oh3fu31tr2 ...................................................................................413

16.C.82. Test run oh3fu40tr1 ...................................................................................414

16.C.83. Test run oh3fu40tr2 ...................................................................................415

16.C.84. Test run oh3fu40tr3 ...................................................................................416

16.C.85. Test run oh3fu40tr4 ...................................................................................417

16.C.86. Test run oh3fu40tr5 ...................................................................................418

16.C.87. Test run oh3fu40tr6 ...................................................................................419

16.C.88. Test run hnitr1 ...........................................................................................420

16.C.89. Test run h2nitr1 .........................................................................................421

16.C.90. Test run ch4ohtr1.......................................................................................422

16.C.91. Test run ch4ohtr2.......................................................................................423

16.C.92. Test run ch4ohtr3.......................................................................................424

16.C.93. Test run ch4ohtr4.......................................................................................425

16.C.94. Test run ch4cltr1........................................................................................426

16.C.95. Test run ch4cltr2........................................................................................427

16.C.96. Test run ch4otr1.........................................................................................428

16.C.97. Test run ohcltr1 .........................................................................................429

16.C.98. Test run ohcltr2 .........................................................................................430

16.C.99. Test run ohcltr3 .........................................................................................431

16.C.100. Test run ohcltr4 .......................................................................................432

16.C.101. Test run ohcltr5 .......................................................................................433

16.C.102. Test run ch3tr1.........................................................................................434

16.C.103. Test run h3o2fu31tr1 ...............................................................................435

16.C.104. Test run h3o2fu31tr2 ...............................................................................436

16.C.105. Test run h3o2fu31tr3 ...............................................................................437

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16.C.106. Test run h3o2fu31tr4 ...............................................................................438

16.D. Summary of test runs .........................................................................................439

17. DESCRIPTION OF FILES IN RELEASE OF VERSION 17 ....................................441

17.A. FORTRAN files and subprograms, MODULE files, and PES subroutines ..........441

17.A.1. Polyrate subprograms .................................................................................441

17.A.2 User-supplied subprograms and module files ..............................................488

17.A.3 FORTRAN files ...........................................................................................488

17.B. Utility program detmi.f.......................................................................................491

17.C. Utility program hrotor.f ......................................................................................493

17.D. Utility programs findl.f and findb.f ....................................................................497

17.E. Utility program rotate30.f, rotate31.f, and rotate40.f .........................................497

17.F. Utility program SS-QRRK...................................................................................500

18. UNIX C SHELL SCRIPTS AND PERL SCRIPTS...........................................................501

18.A. Installation script ................................................................................................501

18.B. Potential energy surface compiling scripts.........................................................502

18.C. Source code compiling script .............................................................................503

18.D. Linking script .....................................................................................................504

18.E. Test run scripts....................................................................................................504

19. FILE USAGE .............................................................................................................505

20. CITATIONS INDICATED BY BRACKETS IN THE TEXT....................................508

21. BIBLIOGRAPHY ......................................................................................................512

22. ERRATA ....................................................................................................................523

23. ACKNOWLEDGMENTS..........................................................................................524

24. INDEX .......................................................................................................................525

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Polyrate 12

Part I General Information

1. INTRODUCTION

Polyrate 17-C (to be called Polyrate for short) is a suite of programs for the analysis of

reactants, products, and transition states of chemical reactions and for calculating

variational transition state theory (VTST) rate constants and multidimensional

semiclassical tunneling probabilities. The program suite consists of the main program,

called POLYRATE, and a number of utility programs. The program performs two

qualitatively different kinds of VTST calculations:

• RP-VTST: reaction–path VTST for arbitrary kinds of reactions with tight

transition states.

• VRC-VTST: variable-reaction-coordinate VTST only for loose transition states of

bimolecular association reactions or their reverse dissociation reactions.

and it also can calculate pressure-dependent rate constants by using system-specific

quantum Ramsperger–Rice–Kassel theory:

• SS-QRRK: system-specific quantum RRK theory

RP-VTST and VRC-VTST are included in Polyrate proper, and SS-QRRK is performed

in a separate utility code that is included as part of the Polyrate package. The SS-QRRK

utility code is described in a separate manual, which is also included as part of the

Polyrate package.

The following articles contain summaries of the technical background for the

methods in Polyrate:

• "Variational Transition-State Theory," D. G. Truhlar and B. C. Garrett, Accounts

of Chemical Research 13, 440-448 (1980).

doi.org/10.1021/ar50156a00220.

• “Generalized Transition State Theory,” D. G. Truhlar, A. D. Isaacson, and B. C.

Garrett, in Theory of Chemical Reaction Dynamics, edited by M. Baer (CRC

Press, Boca Raton, FL, 1985), Vol. 4, pp. 65–137.

comp.chem.umn.edu/Truhlar/docs/C20.pdf

• “Variational Transition State Theory,” D. G. Truhlar and B. C. Garrett, in Annual

Review of Physical Chemistry, Vol. 35, edited by B. S. Rabinovitch, J. M. Schurr,

and H. L. Strauss (Annual Reviews, Inc., Palo Alto, California, 1984), pp. 159–

189.

doi.org/10.1146/annurev.pc.35.100184.001111

comp.chem.umn.edu/Truhlar/docs/C21.pdf

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Polyrate 13

• “POLYRATE: A General Computer Program for Variational Transition State

Theory and Semiclassical Tunneling Calculations of Chemical Reaction Rates,”

A. D. Isaacson, D. G. Truhlar, S. N. Rai, R. Steckler, G. C. Hancock, B. C.

Garrett, and M. J. Redmon, Computer Physics Communications 47, 91-102

(1987).

doi.org/10.1016/0010-4655(87)90069-5

• “Dynamical Formulation of Transition State Theory: Variational Transition States

and Semiclassical Tunneling,” S. C. Tucker and D. G. Truhlar, in New

Theoretical Concepts for Understanding Organic Reactions, edited by J. Bertrán

and I. G. Csizmadia (Kluwer, Dordrecht, The Netherlands, 1989), pp. 291–346.

[NATO ASI Ser. C 267, 291–346 (1989)]

doi.org/10.1007/978-94-009-2313-3_11

comp.chem.umn.edu/Truhlar/docs/UMSI1988-90.pdf

• “POLYRATE 4: A New Version of a Computer Program for the Calculation of

Chemical Reaction Rates for Polyatomics,” D.-h. Lu, T. N. Truong, V. S.

Melissas, G. C. Lynch, Y.-P. Liu, B. C. Garrett, R. Steckler, A. D. Isaacson, S. N.

Rai, G. C. Hancock, J. G. Lauderdale, T. Joseph, and D. G. Truhlar, Computer

Physics Communications 71, 235-262 (1992).

doi.org/10.1016/0010-4655(92)90012-N

• "POLYRATE 6.5: A New Version of Computer Program for the Calculation of

Chemical Reaction Rates for Polyatomics," R. Steckler, W.-P. Hu, Y.-P. Liu, G.

C. Lynch, B. C. Garrett, A. D. Isaacson, V. S. Melissas, D.-h. Lu, T. N. Truong,

S. N. Rai, G. C. Hancock, J. G. Lauderdale, T. Joseph, and D. G. Truhlar,

Computer Physics Communications 88, 341-343 (1995). [new version

announcement] doi.org/10.1016/0010-4655(95)00037-G

• "Transition State Theory," B. C. Garrett and D. G. Truhlar, in Encyclopedia of

Computational Chemistry, edited by P. v. R. Schleyer, N. L. Allinger, T. Clark, J.

Gasteiger, P. A. Kollman, and H. F. Schaefer III (John Wiley & Sons, Chichester,

UK, 1998), Volume 5, pp. 3094-3104.

comp.chem.umn.edu/Truhlar/docs/C58.pdf

• "Variational Transition State Theory and Multidimensional Tunneling for Simple

and Complex Reactions in the Gas Phase, Solids, Liquids, and Enzymes," D. G.

Truhlar, in Isotope Effects in Chemistry and Biology, edited by A. Kohen and H.-

H. Limbach (Marcel Dekker, Inc., New York, 2006), pp. 579-619.

doi.org/10.1201/9781420028027.ch22

• "Variational Transition State Theory in the Treatment of Hydrogen Transfer

Reactions, " D. G. Truhlar and B. C. Garrett, in Hydrogen-Transfer Reactions,

edited by J. T. Hynes, J. P. Klinman, H.-H. Limbach, and R. L. Schowen (Wiley-

VCH, Weinheim, Germany, 2007), Vol. 2, pp. 833-874.

doi.org/10.1002/9783527611546.ch27

comp.chem.umn.edu/Truhlar/docs/C73.pdf

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Polyrate 14

• "Variational Transition State Theory," B. C. Garrett and D. G. Truhlar, in Theory

and Applications of Computational Chemistry: The First Forty Years, edited by

C. E. Dykstra, G. Frenking, K. S. Kim, and G. E. Scuseria (Elsevier, Amsterdam,

2005), pp. 67-87. CODEN: 69HSJX

doi.org/10.1016/B978-044451719-7/50048-2

comp.chem.umn.edu/Truhlar/docs/C71.pdf

• "Variational Transition State Theory with Multidimensional Tunneling," A.

Fernandez-Ramos, B. A. Ellingson, B. C. Garrett, and D. G. Truhlar, in Reviews

in Computational Chemistry, Vol. 23, edited by K. B. Lipkowitz and T. R.

Cundari (Wiley-VCH, Hoboken, NJ, 2007), pp. 125-232.

doi.org/10.1002/9780470116449.ch3

comp.chem.umn.edu/Truhlar/docs/C76.pdf

• “Mechanistic Analysis of the Base-Catalyzed HF Elimination from 4-Fluoro-4-

(4'-nitrophenyl)butane-2-one Based on Liquid-Phase Kinetic Isotope Effects

Calculated by Dynamics Modeling with Multidimensional Tunneling,” Y. Kim,

A. V. Marenich, J. Zheng, K. H. Kim, M. Kołodziejska-Huben, M. Rostkowski,

P. Paneth, and D. G. Truhlar, Journal of Chemical Theory and Computation 5, 59-

67 (2009).

doi.org/10.1021/ct800345j

• “Multi-path Variational Transition State Theory for Chemical Reaction Rates of

Complex Polyatomic Species: Ethanol + OH Reactions,” J. Zheng and D. G.

Truhlar, Faraday Discussions 157, 59-88 (2012).

doi.org/10.1039/C2FD20012K.

• “Association of CF2 and Dissociation of C2F4 by Variational Transition State

Theory and System-Specific Quantum RRK Theory,” J. L. Bao, X. Zhang, and D.

G. Truhlar, Proceedings of the National Academy of Sciences U.S.A. 113, 13606-

13611 (2016).

doi.org/10.1073/pnas.1616208113

• “Variational Transition State Theory: Theoretical Framework and Recent

Developments,” J. L. Bao and D. G. Truhlar, Chemical Society Reviews 46,

7548-7596 (2017).

doi.org/10.1039/C7CS00602K

• “Semiclassical Multidimensional Tunneling Calculations,” D. G. Truhlar, in

Tunnelling in Molecules: Nuclear Quantum Effects from Bio to Physical

Chemistry, edited by J. Kaestner and S. Kozuch (RSC Publishing, Cambridge,

2021), pp. 261-282.

doi.org/10.1039/9781839160370-00261

https://truhlar.dl.umn.edu/sites/truhlar.dl.umn.edu/files/c88corrected_proofs.pdf

In Polyrate, analysis of reactants and products can be performed for up to two

reactants and two products for RP-VTST and for two reactants and one product for VRC-

VTST. Polyrate also calculates equilibrium constants and reverse reaction rates, so the

VRC-VTST method can also calculate rate constants for one reactant and two products.

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Polyrate 15

The RP-VTST method can be applied to gas-phase, liquid-phase, solid-phase, and gas-

solid-interface reactions; the VRC-VTST method is used for gas-phase reactions.

Generalized transition state theory calculations may be carried out using the

harmonic approximation for vibrations with either rectilinear or curvilinear coordinates in

RP-VTST calculations. It is highly recommended to use curvilinear coordinates (via the

“CURV2” or “CURV3” options) rather than Cartesian coordinates for generalized-

normal mode analysis along the MEP in RP-VTST calculations; Cartesian coordinates

will often yield unphysical imaginary frequencies along the reaction coordinate, and these

will cause unphysical VTST results. One should always check in the long output that the

generalized normal mode frequencies as functions of the reaction coordinate do not

contain any imaginary frequencies transverse to the reaction path; imaginary frequencies

may lead to unreliable or wrong results.

A limited amount of nontorsional anharmonicity may also be included, but a very

important feature of Polyrate is its ability to handle multistructural and torsional-potential

anharmonicity by utilizing the Polyrate in conjunction with the MSTOR program. See

Section 10.O.

The RP-VTST rate constants can be computed using canonical variational theory

(CVT), and microcanonical variational theory (VT). Conventional transition state theory

(TST) may also be employed. VRC-VTST calculations currently only can be applied to

gas-phase reactions using CVT, VT, and total energy and total angular momentum-

resolved microcanonical variational theory, which for short may be called E,J-resolved

microcanonical variational theory (E,J-VT).

For thermal or ground-state reactions using RP-VTST, tunneling probabilities can

be computed using the zero-curvature tunneling method (ZCT), the small-curvature

tunneling (SCT) method, the large-curvature tunneling (LCT) method, or an optimized

multidimensional tunneling method (OMT or COMT). The SCT calculations are based

on the centrifugal-dominant small-curvature semiclassical ground-state (CD-SCSAG)

method, and the LCT calculations are based on the large-curvature ground-state method,

version 3 or 4 (LCG3 or LCG4. For state-selected excited-state reactions only the ZCT

and SCT methods are available in this version. In addition, for ground-state reactions of

exoergic or thermoneutral reactions, LCT calculations may be summed over certain

excited final states, and for endoergic reactions, LCT calculations may be summed over

certain excited states of reactants. (These summations are a required part of the method

when these contributions are not negligible). The recommended tunneling procedure

when LCT calculations are carried out is the microcanonical optimized multidimensional

tunneling method (OMT) in which, at each energy, the tunneling probability is

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Polyrate 16

approximated as the larger of the values calculated by the SCT and LCT methods. The

option of carrying out a tunneling calculation is not available in conjunction with VRC-

VTST option.

The Polyrate program computes rate constants by either single-level or dual-level

approaches for RP-VTST calculations and by single-level approach for VRC-VTST

calculations.

The single-level calculations and the lower level of dual-level calculations using

RP-VTST may be based on either an analytic potential energy function, which is called

the potential energy surface (PES) or potential energy function (PEF), or on various

types of interpolations of electronic structure input data at selected points along the

minimum energy path. VRC-VTST calculations can only be used for single-level

calculations based on a global PES or direct dynamics interfaced with an electronic

structure package.

When using a PES, the user must supply a subroutine, which, for a given set of

Cartesian coordinates of each of the atoms, returns the potential energy and its first

derivatives with respect to the Cartesian coordinates. This subroutine is called by a set of

Polyrate interface routines called hooks. (In particular, the “hooks” consist of

subprograms PREP, PREPJ, EHOOK, GHOOK, HHOOK, and OHOOK plus a few utilities, e.g.,

YTRANS and YNEWT, that are discussed in Section 8.C.). Note that VRC-VTST

calculations don’t need gradient information if optimized geometries and vibrational

frequencies of reactants and/or product are provided in the input file. When using

electronic structure input data without an analytic surface, the user must supply, as an

input file to the program, the geometries, energies, and force constants or frequencies for

the reactants, products, and saddle point, and optionally these quantities and the gradient

at a sequence of points on the minimum energy path. These data are then used for

dynamics calculations.

For RP-VTST calculations using dual-level approach, the data along the reaction

path may be “corrected” using higher-level data supplied by the user at selected points

either for reaction paths based on potential energy surfaces or for those based on

electronic structure input files. A generic name for such dual-level RP-VTST methods is

VTST-IOC. We currently recognize three variants of the IC methods, namely IOC

(interpolated optimized corrections), IOE (interpolated optimized energies), and ISPE

(interpolated single point energies). The IOC and IOE methods are also called triple-

slash (///) VTST. In the IOC method, the frequencies, potential energies, and moment-of-

inertia determinants along the reaction path that are calculated from the potential energy

surface are “corrected” using the results of higher-level electronic structure calculations

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Polyrate 17

(supplied by the user) at selected points. The O in IOC indicates that any corrections at

stationary points are based on geometries optimized at the higher level. If corrections

were made at nonstationary points, they would be based on reaction paths calculated at

the higher level. The IOE approach is a subcase of IOC in which only the energies and

moment-of-inertia determinants are corrected, but the corrected energies are based on

geometries optimized at the higher level. The final dual-level method, called VTST-

ISPE, corrects only the energies along the reaction path using higher-level electronic

structure calculations (supplied by the user) at the stationary points and selected points

along the path. This kind of calculation is called a double-slash (//) calculation. In general

the acronyms VTST-IOC and VTST-IOE or the triple slash notation is reserved for cases

when the correction involves a higher-level geometry optimization of the transition state.

The VTST-ISPE notation refers to using higher-level single-point energies at the lower-

level saddle point or at the lower-level saddle point plus selected points along the lower-

level reaction path. Thus VTST-IOE is expected to be more accurate than VTST-ISPE,

even though one neglects the corrections to the frequencies.

In addition to the straight VTST method and to dual-level VTST-IOC and VTST-

ISPE, the code also has single-level IVTST options for RP-VTST calculations. With the

IVTST philosophy the user supplies the geometry, energy, and frequencies or Hessian at

the stationary points and additionally at as many points along the path as are

computationally feasible. Polyrate has the functionality to perform VTST calculations

with information at the stationary points and no points along the reaction path, called

IVTST-0, with one point along the path on either side of the saddle point, called IVTST-

1, or with an arbitrary number of points along the path on either side of the saddle point

(as long as there is at least one nonstationary point on either side of the saddle point).

The latter option is carried out by the mapped interpolation (MI) algorithm and is called

IVTST-M. In the current version of POLYRATE, IVTST-M is available with only the

default IVTST-M options when electronic structure input data is read from file fu30 or

fu40, and it is available with all the IVTST-M options for files fu31 and the hooks. Note

that IVTST-M can also be used as the lower level of a dual-level calculation, but in the

present version of Polyrate, IVTST-0 and IVTST-1 cannot be used that way.

In addition to the use of the MI algorithm as the central element of the IVTST-M

method with electronic structure input files, since version 8.0 of Polyrate we have

allowed the use of the MI algorithm as an "extrapolation" algorithm when using the

hooks for a calculation with a saddle point. If the hooks are used to interface with an

electronic structure calculation, this provides an alternative way to perform IVTST-M

direct dynamics calculations. If the hooks are used with an analytic potential, this

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Polyrate 18

replaces the previously used method for extrapolating the adiabatic potential and

effective masses beyond the edge of the originally calculated grid. Finally we note that

the energy part of the MI algorithm is used in the VTST-ISPE version of VTST-IC.

There is also an option, called the RESTART option, in which the input consists in

part of reaction-path information calculated in a previous run of the program. The

RESTART option is not available for dual-level calculations.

Interface versions of POLYRATE, called CHARMMRATE, GAMESSPLUSRATE,

GAUSSRATE, JAGUARATE, MC-TINKERATE, MORATE, MULTILEVELRATE, and NWCHEMRATE,

which compute rate constants from potentials, gradients, and Hessians calculated by

electronic structure methods, are also available

CHARMMRATE is a module of the CHARMM program; CHARMMRATE can compute

enzyme-catalyzed rates by ensemble-averaged VTST. An interface to the CHARMMRATE

module of the CHARMM package based on Polyrate version 9.0, called CRATE, is available

as a separate distribution.

An interface to the GAMESSPLUS (or GAMESS) electronic structure packages based on

Polyrate version 9.3, called GAMESSPLUSRATE, is available as a separate distribution.

An interface to the GAUSSIAN16 (or GAUSSIAN98 or GAUSSIAN03 or GAUSSIAN09)

electronic structure packages based on Polyrate version 2017, called GAUSSRATE, is

available as a separate distribution.

An interface to the JAGUAR package based on Polyrate version 9.6, called

JAGUARATE, is available as a separate distribution.

An interface to the MC-TINKER package based on Polyrate version 9.1, called MC-

TINKERATE, is available as a separate distribution.

MORATE uses the semiempirical molecular orbital package MOPAC instead of an

analytic potential energy function. The electronic structure input file option and MORATE

are both examples of direct dynamics, i.e., rate or dynamics calculations based directly on

electronic structure information without the intermediary of an analytic fit to the potential

energy surface. The MORATE program is not distributed as part of the Polyrate package,

but it is available as a separate distribution from the University of Minnesota.

An interface to the MULTILEVEL package based on Polyrate version 9.1, called

MULTILEVELRATE, is available as a separate distribution.

An interface to the NWCHEM package based on Polyrate version 9.7, called

NWCHEMRATE, is available as a separate distribution.

AMSOLRATE is an interface with the AMSOL electronic structure package.

AMSOLRATE can also calculate rate constants for reactions in liquid-phase solutions.

AMSOLRATE can also be used for gas-phase calculations with semiempirical molecular

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Polyrate 19

orbital theory, but we recommend MORATE for that purpose because it produces less

noisy frequencies. Therefore we do not mention AMSOLRATE in most lists of available

interface programs.

The various direct dynamics methods obtain their input about the system in

different ways:

• Single-level direct dynamics calculations may be carried out using file fu29,

file fu30, file fu31, file fu40, or file fu50 for the electronic structure

information (RP-VTST).

• VTST-IOC dual-level direct dynamics calculations may be carried out using

file fu30, fu31, or file fu40 for the lower-level information and file fu50 for

the higher-level information (RP-VTST).

• VTST-ISPE dual-level direct dynamics calculations may be carried out using

file fu30, fu31, or file fu40 for the lower-level information and file fu51 for

the higher-level information (RP-VTST).

• Single-level calculations based on an analytic potential energy surface obtain

the potential surface information from subprograms SETUP and SURF, which

are called by the hooks (RP-VTST and VRC-VTST).

• VTST-IOC dual-level calculations based on an analytic potential energy

surface for the lower level obtain the potential surface information from

subprograms SETUP and SURF (called by the hooks) and they obtain the higher-

level electronic structure information from file fu50 (RP-VTST).

• VTST-ISPE dual-level calculations based on an analytic potential energy

surface for the lower level obtain the potential surface information from

subprograms SETUP and SURF (called by the hooks) and they obtain the higher-

level electronic structure information from file fu51 (RP-VTST).

We note that files fu30, fu31, and fu40 accomplish essentially the same purpose.

There are two differences between fu30 and fu40 is that file fu30 requires formatted data,

whereas file fu40 is based on keyword input. The second difference is that there is a

WRITEFU30 keyword, but again there is no WRITEFU40 keyword. File fu31 is also based

on keyword input, but it differs from file fu40 in that certain IVTST-M options are

supported with fu31 but not with fu40. A second difference is that there is a WRITEFU31

keyword, but there is no WRITEFU40 keyword. See also Sect. 11.D.1. At some point in

the future we may stop supporting fu30, but for now we will keep it for the convenience

of users of previous versions. New users are encouraged to ignore fu30 and to use fu31

instead.

Throughout this manual it will be useful to keep in mind that there are really several

types of single-level VTST calculations, namely

1. Straight VTST

1.A. Straight VTST through the hooks

1.B. Straight VTST with file fu30 or file fu40

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Polyrate 20

2. IVTST-M

2.A. IVTST-M with file fu30 or fu40

2.B. IVTST-M with file fu31

3. IVTST-0 or IVTST-1.

Note that RP-VTST calculations can be performed using any of these options, but

VRC-VTST calculations can only be performed using option 1.A. Calculations of type

1.A, 1.B, 2.A, and 2.B have many points of similarity, and in fact once Polyrate has all

the save grid arrays filled with data, these types of runs become identical. Further the MI

algorithm that constitutes the central element of IVTST-M calculations (2.A or 2.B) can

also be used in straight VTST (1.A or 1.B), but for straight VTST is considered as an

algorithm for extending the save grid to improve numerical convergence rather than

being considered as the main ingredient of the method. However runs of type 3 do not

use the save grid. In this manual we try to alert the reader whether a statement is true for

one or another of these types of calculations, but not for all four types. However, the

reader should be aware that sometimes we fail to mention this because it is assumed clear

from the context or because the manual needs more work.

Dual-level calculations can be performed with type 1.A, 1.B, 2.A, or 2.B

calculations as the lower level.

The main options for RP-VTST calculations are summarized in the following table:

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Polyrate 21

Dynamics

approach

hooks fu29 fu30, fu31, or

fu40

fu50

TST TST TST TST TST

VTST TST/ZCT

CVT

CVT/ZCT

CVT/SCT

CVT/LCT

VT

VT/ZCT

VT/SCT

VT/LCT

TST/ZCT

CVT

CVT/ZCT

CVT/SCT

VT

VT/ZCT

VT/SCT

IVTST-0 TST

TST/ZCT

TST

TST/ZCT

IVTST-1 TST

TST/ZCT

CVT

CVT/ZCT

CVT/SCT

hooks

plus fu50

fu30, fu31, or

fu40 plus fu50

VTST-IOC TST

TST/ZCT

CVT

CVT/ZCT

CVT/SCT

CVT/LCT

TST

TST/ZCT

CVT

CVT/ZCT

CVT/SCT

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Polyrate 22

Table continued:

Dynamics

approach

hooks

plus fu50

fu30, fu31, or

fu40 plus fu50

VTST-IOC VT

VT/ZCT

VT/SCT

VT/LCT

VT

VT/ZCT

VT/SCT

hooks

plus fu51

fu30, fu31, or

fu40 plus fu51

VTST-ISPE VT

VT/ZCT

VT/SCT

VT

VT/ZCT

VT/SCT

Note that whenever both SCT and LCT methods are available, then the µOMT method is

available as well.

Also note: When an analytical potential is used, the hooks call SETUP and SURF.

However, the hooks capability is more general, and the hooks can be used to interface

Polyrate with electronic structure codes for direct dynamics; examples are the CRATE,

GAMESSPLUSRATE, GAUSSRATE, JAGUARATE, MC-TINKERATE, MORATE, MULTILEVELRATE,

and NWCHMERATE programs, which are interfaces to CHARMM with the CHARMMRATE

module, GAMESSPLUS, GAUSSIAN, JAGUAR, MC-TINKER, MOPAC, MULTILEVEL, and

NWCHEM, respectively.

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Polyrate 23

2. RECOMMENDED CITATION FOR POLYRATE 17-C

The recommended CITATION for the Polyrate code is

J. Zheng, J. L. Bao, R. Meana-Pañeda, S. Zhang, B. J. Lynch, J. C. Corchado, Y.-Y.

Chuang, P. L. Fast, W.-P. Hu, Y.-P. Liu, G. C. Lynch, K. A. Nguyen, C. F. Jackels,

A. Fernandez Ramos, B. A. Ellingson, V. S. Melissas, J. Villà, I. Rossi, E. L. Coitiño, J.

Pu, T. V. Albu, A. Ratkiewicz, R. Steckler, B. C. Garrett, A. D. Isaacson, and

D. G. Truhlar, Polyrate 17-C, University of Minnesota, Minneapolis, 2018.

https://comp.chem.umn.edu/polyrate/

References for methods used in the code are given in Sect. 21 of this manual.

3. RECOMMENDED CITATIONS FOR INCORPORATED CODE

1. The code for evaluating the Cartesian B matrix and C tensor for stretches,

nondegenerate bends, and torsions for the general polyatomic case is from J.

Cioslowski and M. Challacombe, ANHTRAX, QCPE Program No. 609 (Quantum

Chemistry Program Exchange, Bloomington, IN, 1991). (used with permission)

2. The EF code for stationary point optimization is from J. Barker, F. Jensen, H. S. Rzepa,

A. Stebbings, LOCATION OF TRANSITION STATES IN AMPAC AND MOPAC USING

EIGENVECTOR FOLLOWING (EF), QCPE Program No. 597 (Quantum Chemistry Program

Exchange, Bloomington, IN, 1990). (used with permission)

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4. LICENSING

Polyrate 17-C is licensed under the Apache License, Version 2.0.

The manual of Polyrate 17-C is licensed under CC-BY-4.0.

Publications of results obtained with the Polyrate 17-C software should cite the program

and/or the article describing the program.

No guarantee is made that this software is bug-free or suitable for specific applications,

and no liability is accepted for any limitations in the mathematical methods and

algorithms used within. No consulting or maintenance services are guaranteed or implied.

The use of the Polyrate 17-C implies acceptance of the terms of the licenses.

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5. PROGRAM AND MANUAL DESCRIPTION

5.A. Code description, portability, and special files

The Polyrate program is written in FORTRAN 90 with the module and dynamically

allocated memory features.

Users should be aware that, beginning with version 2008, Polyrate can perform two kinds

of calculations. One is RP-VTST, and the other one is VRC-VTST, as explained in

Section 1. These two kinds of calculations involve different subroutines to generate

different executable programs. RP-VTST has both serial and MPI parallel versions and

VRC-VTST has only an MPI parallel version and requires one to link to the SPRNG

library. Starting with version 2010, the SPRNG package is included in the Polyrate

distribution for the user’s convenience, and the Polyrate installation script includes

compiling the SPRGN library before linking Polyrate subroutines to this library.

Therefore installation of SPRNG library and Polyrate program can be done with one

script. To use RP-VTST, no pre-installed library or package is required.

The SPRNG package can be also obtained separately from the web page:

http://sprng.cs.fsu.edu/

5.B. Description of the manual

This manual is divided into five parts.

Part I has five sections and includes general information about POLYRATE.

Part II has five sections and includes theoretical background and computational details

for RP-VTST. Section 6 provides an overview of theoretical background for the

dynamical calculations. Section 7 gives information related to the program structure.

Sections 8 and 9 describe the calculations using a potential energy surface (Section 8) or

direct dynamics calculations, which use an electronic structure input file (Section 9).

Section 10 provides selected details of the calculations, especially for procedures that are

not fully described in publications.

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Part III has one section, Section 11, to describe the theoretical background of VRC-

VTST.

Part IV has 3 sections for description of input files. Section 12 describes the complete

Polyrate input and selected aspects of the output for RP-VTST calculations. Section 13

describes the input file for VRC-VTST. Section 14 describes files that give extra details

of LCT calculations.

Part V gives more general information about the Polyrate program package. Section 15

contains instructions on how to install, test, and use the Polyrate program. Section 16

gives sample runs (the Polyrate test suite) that may be useful in understanding the input

or testing the program. Section 17 lists the files in the program distribution, and it has a

brief explanation of each subprogram. Section 18 contains instructions on using the Unix

scripts that are provided. Section 19 describes file usage. Section 20 provides references

indicated by brackets in the text of the manual, and Section 21 is the Polyrate

bibliography.

Much of the mathematical formulation underlying the dynamical calculations is presented

in a book chapter entitled “Variational Transition State Theory with Multidimensional

Tunneling,” which is Ref. 71 in the bibliography (Sect. 21), and should be consulted

along with this manual. “Generalized Transition State Theory“ (GTST), which is Ref. 5

in Sect. 21, is also a useful chapter, especially for an introduction to the older core ideas,

although Ref. 71 supersedes it. If these books are unavailable in your library, you may

obtain a copy of the chapters from the senior author (DGT) at

http://comp.chem.umn.edu/Polyrate

A PDF file with a complete compilation of all known errors in Ref. 5 is also given at this

Web site.

5.B.1. Referencing conventions

Reference numbers in this manual refer to references in Sect. 20. In all cases the

reference number is accompanied by the section number to avoid confusion.

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5.B.2. Key references

Reference 5 in Sect. 21 is sometimes referred to simply as "the GTST book chapter":

“Generalized Transition State Theory”, D. G. Truhlar, A. D. Isaacson,

and B. C. Garrett, in The Theory of Chemical Reaction Dynamics, edited

by M. Baer (CRC Press, Boca Raton, FL, 1985), Vol. 4, pp. 65-137.

Reference 71 in Sect. 21 is sometimes referred to as “the VTST/MT book chapter”:

"Variational Transition State Theory with Multidimensional Tunneling,"

A. Fernandez-Ramos, B. A. Ellingson, B. C. Garrett, and D. G. Truhlar,

in Reviews in Computational Chemistry, Vol. 23, edited by K. B.

Lipkowitz and T. R. Cundari (Wiley-VCH, Hoboken, NJ, 2007), pp.

125-232.

These two book chapters explain the methods used in Polyrate up to 2005. PDF files of

these chapters are available at the Polyrate Web site:

http://comp.chem.umn.edu/polyrate

All known errata to the GTST book chapter have been assembled into a PDF file. This

file is also available at the Polyrate Web site.

A review that also covers the more recently developed methods is also available: Ref.

114 in Sect. 21:

“Variational Transition State Theory: Theoretical Framework and

Recent Developments,” J. L. Bao and D. G. Truhlar, Chemical Society

Reviews 46, 7548-7596 (2017). doi.org/10.1039/C7CS00602K

Taken together, these three articles explain almost all the methods used in Polyrate.

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Part II Theory Background and Calculation Details on RP-VTST

6. THEORETICAL BACKGROUND ON RP-VTST

This section provides an overview of the dynamical theory underlying the calculation

procedures. Further details of the methods for gas-phase bimolecular and unimolecular

reactions may be found in the "Generalized Transition State Theory" (GTST) book

chapter (Ref. 5, Sect. 21). Details of new methods developed after that chapter was

written are described in Section 10 of this manual, if not fully published, or in the

additional references in Sect. 21, especially the VTST/MT book chapter (Ref. 70 of Sect.

21) and the most recent review (Ref. 114 of Sect 21).

6.A. Basic theory

As described in the Introduction, the program can be used to calculate rate constants for

reactions of one or two reactant molecules to form one or two product molecules, using a

variety of generalized transition state theory methods. In order to simplify the

discussions in the remainder of this introductory overview section, we consider only the

calculation of forward and reverse thermal rates using both conventional transition state

theory (TST) and canonical variational theory (CVT). Microcanonical variational theory

(µVT) are described in detail in the GTST book chapter. The applications of VTST

methods to gas-phase unimolecular or bimolecular reactions or gas-solid-interface

reactions or the calculation of adiabatic and diabatic state-selected rate constants are

described in the references included in Sect. 21.

The improved canonical variational theory (ICVT) option has been removed from

Polyrate. If one sees a need for the more accurate threshold treatment of ICVT, one

should instead use µVT because µVT is coded in Polyrate with the extended Beyer-

Schwinehart (BS) algorithmfor calculating number of available state, and this iss more

efficient and more complete than IVCT.

The conventional transition-state-theory canonical rate constant involves a symmetry

number [Ref. 1, Sect. 22] times kT/h times a ratio of a partition function evaluated at the

saddle point to one evaluated at the reactants, and, optionally, times a temperature-

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dependent transmission coefficient, which in this program, takes into account tunneling

and non-classical reflection effects. The partition functions are evaluated as products of

electronic, vibrational, and rotational partition functions, and for the reactants of a

bimolecular reaction, a relative translational partition function per unit volume. In

Polyrate, vibrational partition functions are defined such that they tend to a Boltzmann

factor of the zero point energy at low temperature (not to unity as is common in statistical

mechanics books), and the corresponding local zero of energy is used consistently for the

rest of the calculations.

To calculate rate constants by the CVT method various items of information are needed

along the reaction path. In Polyrate, the reaction path is always taken as the minimum

energy path (MEP) through mass-scaled (i.e. isoinertial) coordinates [Refs. 2-5, Sect. 22]

except for the treatment of loose transition state using variable-reaction-coordinate

(VRC) algorithm with single-faceted or multifaceted (MF) dividing surface (the VRC

algorithm and MF dividing surfaces are discussed in detail in Section 11). The

descriptions here are all referred to MEP. Following Fukui [Ref. 5, Sect. 22], one may

call this the "intrinsic" reaction path. (In Polyrate, we always call it the MEP.) The

distance along the MEP is called s, or the reaction coordinate. For reactions with a saddle

point, the MEP is specifically defined to be the path of steepest descent through mass-

scaled Cartesian coordinates from the saddle point (s = 0) to the reactants (at which s

= – for a bimolecular reaction, or s equals a finite negative number for a unimolecular

reaction) and the path from this saddle point to the products (at which s = + for a

bimolecular reaction, or s equals a finite positive number for a unimolecular product).

We define a sequence of generalized transition states corresponding to the reaction

coordinate to be hypersurfaces which are orthogonal to the MEP [Ref. 6, Sect. 22]. All

quantities calculated for a generalized transition state that intersects the MEP at a

particular value s of the reaction coordinate are labeled by that value of s (as well as the

temperature T when they depend on temperature). The generalized TST canonical

forward rate constant

 

kfGT(T,s) is then evaluated like the conventional one but with

saddle point properties replaced by generalized transition-state (GT) ones. Thus, at each

generalized transition state along the reaction path the following information is (or may

be, depending on the options chosen) needed:

 

VMEP(s) — potential along the minimum energy path,

|I(s)| — determinant of the moment of inertia tensor,

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X(s) — geometry of the generalized transition state,

— the gradient of the generalized transition state,

 

Lm(s) — eigenvector of the generalized normal mode m,

 

wm(s) — generalized normal mode frequencies.

In addition, depending on the anharmonicity option and the method chosen to include

tunneling, one may also require some or all of the following additional functions:

 

km(3)(s) — principal cubic force constants for the generalized normal

modes,

 

km(4)(s) — principal quartic force constants for the generalized normal

modes,

BmF(s) — reaction-path curvature coupling [Ref. 7, Sect. 22] between

the reaction coordinate (mode F) and generalized normal

mode m. Sometimes we refer to the set of BmF(s) with m=1,

2, ..., F-1, as the curvature vector BF.

Note that “principal” force constants are diagonal in the normal mode index; that is why

k3(s) and k4(s) are short one-dimensional arrays. The functions listed above and the

reaction path itself can be obtained through the hooks, which can in turn be interfaced to

an analytic potential energy surface or an electronic structure package, or alternatively

this data (or information which can be used to calculate this data) can be obtained from

electronic structure calculations carried out separately from Polyrate. In the latter case

the MEP information is input only on a relatively sparse grid of s values, and the program

interpolates this information to arbitrary s values. This option is called the electronic

structure input file option (POTENTIAL = unit30, unit31, or unit40).

The isoinertial coordinate system used by Polyrate is defined by eq. (2) of Ref. 1 of Sect.

21 or, equivalently, by eq. (2) of Ref. 5 of Sect. 21. These coordinate systems have the

same reduced mass, µ, for all degrees of freedom. Physical observables and the MEP are

independent of µ, but numerical values of s are not. Thus it is essential to specify if s

values or plots of barriers vs. s are considered. If is set equal to 1 amu, then the

numerical value of s in mass-scaled coordinates (which have units of length) is the same

as the numerical value of the distance along the usual spectroscopists’ mass-weighted

coordinates (which have units of mass 1/2 length) if the mass weighting is amu1/2.

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Therefore setting equal to 1 amu procedure is especially recommended if the goal is to

make the treatment transparent to those who are only used to the spectroscopists’ mass

weighting scheme.

The reverse rate constant is obtained from the forward one by detailed balance. The

canonical variational theory [Ref. 6, Sect. 22] forward rate constant is obtained by

minimizing the generalized transition state theory rate constant with respect to s:

 

k fCVT T( ) = min

sk f

GT T,s( ) = k fGT T,s*

CVT T( )[ ] (1)

Generalized-transition-state-theory rate constants can also be written in terms of the

generalized transition-state (GT), standard-state (0), forward (f) free energy of activation,

. The location of the variational transition state is then determined by

maximizing the free energy of activation with respect to s.

Section 6.C gives a brief explanation of the evaluation of the partition functions and

Section 6.D summarizes methods used for transmission coefficients.

6.B. Vibrations, Rotations, and Translations

This section gives a brief explanation of how Polyrate uses the SPECIES keyword (see

Section 12.A.6) to determine the number of rotations and vibrations used in calculating

the partition functions and the number of degrees of freedom which are projected out by

the projection operator (when the PROJECT option is on, see Section 12.A.6) for the given

reactant, product, transition state, or generalized transition state. The table below gives

the valid values of the SPECIES keyword and a description of what the values mean, along

with the number of vibrations and rotations in the partition function for each type of

species, and the number of modes which are projected out to remove translations,

rotations, and the reaction coordinate.

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Description SPECIES

keyword value

Partition Function Projection Operator

Vibrations Rotations Translations Rotations Reaction

Coordinate

Mandatory?

atomic

reactant or

product

atomic 0 0 … … … N.A.

linear

reactant or

product

linrp 3N – 5 2 3 2 0 optional

nonlinear

reactant or

product

nonlinrp 3N – 6 3 3 3 0 optional

solid-state

reactant or

product

ssrp 3N 0 0 0 0 prohibited

linear

transition

state

lints 3N – 6 2 3 2 0 optional

nonlinear

transition

state

nonlints 3N – 7 3 3 3 0 optional

solid-state

transition

state

ssts 3N – 1 0 0 0 0 prohibited

linear GTS N.A. 3N – 6 2 3 2 1 mandatory

nonlinear

GTS

N.A. 3N – 7 3 3 3 1 mandatory

solid-state

GTS

N.A. 3N – 1 0 0 0 1 mandatory

N.A., Not Applicable; N, number of atoms

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For an atomic reactant or product the value atomic should be specified for SPECIES.

Since the species is a single atom there are no vibrations or rotations, nor is there any

Hessian to consider projecting. Therefore the PROJECT keyword (see Section 12.A.6)

cannot be used with an atomic species.

Gas-phase reactants and products that are not atomic and transition states can be either

linear or nonlinear, specified by linrp, nonlinrp, lints, and nonlints

respectively. After removing the 2 rotations and three translations for a linear molecule

there are 3N – 5 vibrations for the linear species, and after removing the 3 rotations and 3

translations for a nonlinear molecule there are 3N – 6 vibrations for a nonlinear species.

A gas-phase transition state has one additional mode removed due to the reaction

coordinate and therefore has 3N – 6 real vibrations for a linear molecule and 3N – 7 real

vibrations for a nonlinear molecule. The number of vibrations for a generalized transition

state is calculated in the same manner as for a conventional transition state (which is a

saddle point, also called a transition structure). Projecting the Hessian at a transition state

is not required, but sometimes it leads to a more stable calculation of vibrational

frequencies and eigenvectors, so it is a recommended option to project out translations

and rotations at a reactant, product, or transition state. For generalized transition states

(points on the reaction path where the gradient does not vanish), projecting out the

reaction coordinate is mandatory if the resulting frequencies are to represent motions

orthogonal to the reaction coordinate. In such cases it is also mandatory to project out

translations and rotations, if they exist (they always exist for gas-phase cases, but not for

solid-state cases).

Solid-state species are different than gas-phase species as concerns the number of

vibrations. For solid state species there are no rotations or translations which are

removed because a rotation or a translation of a species relative to a surface changes the

potential energy of the whole system. Therefore there are 3N vibrations for a reactant or

product species and 3N – 1 for a transition state or generalized transition state species.

The reaction coordinate is removed for a solid-state species in the same manner as it is

for a gas-phase species.

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6.C. Partition functions

The electronic partition function for a given species is computed quantum mechanically

by summing over the Boltzmann factors of the electronic energy levels of the species

times their degeneracies. In practice, since the energy spacing between electronic

multiplets is generally quite large, we usually include in the summation only those levels

comprising the energetically lowest multiplet, e.g., the J = 0, 1, and 2 levels of O(3P).

The rotational partition function is approximated by the classical limit [Refs. 8 and 9,

Sect. 22]. For a linear reactant, product, transition state, or generalized transition state,

the partition function is evaluated from the unique moment of inertia. For a nonlinear

species, the product of the three principal moments of inertia is required and is

conveniently obtained from the determinant of the moment of inertia tensor. All

symmetry numbers are left out of all rotational partition functions; the symmetry numbers

need only to be included in the overall symmetry number mentioned above [Ref. 1, Sect.

22].

For bimolecular reactions, the relative translational partition function per unit volume is

calculated classically.

For vibrational partition functions, a separable approximation is assumed, whereby the

overall vibrational partition function is a product of independent normal modes of a

reactant, product, or saddle point or the generalized normal modes of a generalized

transition state. Vibrational modes are treated classically or quantized, either quantum

mechanically or semiclassically. Anharmonic methods are limited to intramode

anharmonicity in normal modes expressed as linear combinations of rectilinear

coordinates and do not include mode-mode coupling as a supported option at this time.

The torsional potential anharmonicity along reaction path can be included using the

formula of the multi-structural torsional method but only with one input structure.

Classical vibrational partition functions are evaluated using the classical expression for

the harmonic oscillator. Quantum mechanical vibrational partition functions are

evaluated by the harmonic approximation, by summing Boltzmann factors using quantum

or semiclassical energy levels.

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Frequencies can be scaled for partition function calculations in CVT calculations when

the harmonic approximation is employed. The scaling is not used in the calculation of

transmission coefficients (either by CAG or tunneling).

6.D. Tunneling methods

Different semiclassical methods are used to evaluate transmission coefficients depending

on the degree of coupling between the MEP and other degrees of freedom through the

MEP curvature. There are three general types of transmission coefficients:

zero-curvature tunneling (ZCT), small-curvature tunneling (SCT) and large-curvature

tunneling (LCT). The methods included in this version for each type of transmission

coefficient for thermal reactions are as follows:

ZCT: minimum-energy-path semiclassical adiabatic ground-state

(MEPSAG) method [Refs. 4 and 10, Sect. 22 and Ref. 5, Sect. 21].

SCT: centrifugal-dominant small-curvature semiclassical adiabatic

ground-state (CD-SCSAG) method [Refs. 29 and 31, Sect. 21].

LCT: large-curvature ground-state version-3 (LCG3) method [Refs. 5, 21,

29, 30, and 34, Sect. 21] and large-curvature ground-state version-4

(LCG4) method [Ref. 54, Sect. 21].

The current theory of these tunneling methods appears in “Variational Transition State

Theory with Multidimensional Tunneling,” which is Ref. 59. The final version

(CD-SCSAG, which replaced the original SCSAG) of the SCT method is described in

Refs. 29 and 31 in Sect. 21, and the final versions of the LCT method are described in

Refs. 29, 30, 34 (LCG3 including tunneling into excited states), and Ref. 54 (LCG4

including tunneling into excited states) in Sect. 21. The final versions of these methods

were used in all references of Sect. 21 that have reference number 30 or higher. A

critical element of the SCT calculation is that the reduced mass, (See Section 6.A), is

replaced by an effective mass meff s( ) in calculating the tunneling probabilities. See

Section 6.I of this manual for further discussion.

Notice that the G in MEPSAG, CD-SCSAG, LCG3, and LCG4 refers to the fact that the

transmission coefficient for thermal reactions is always calculated for the ground (G)

state of the reactants in the exoergic direction of a reaction, as discussed elsewhere (Ref.

[13] Sect. 22 and Refs. 29, 30, and 34 of Sect. 21). The transmission coefficient for the

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endoergic direction of a reaction is then obtained by detailed balance, which requires that

the transmission coefficients for thermal reactions be the same in both directions. The

LCG3 and LCG4 methods can include tunneling into excited states of the product in the

exoergic direction, and the algorithm in Polyrate is general enough to treat even cases

that involve a well on the product side in the exoergic direction. (Wells on the reactant

side do not require special considerations in this regard.) The ground-state

approximation for the transmission coefficient is equivalent to assuming that the energy-

dependent transmission probability curve for each successive quantized level of the

transition state has the same functional dependence on energy as that for the ground state

but is shifted up in energy by the excitation energy evaluated at the variational transition

state [Ref. 47, Sect. 22].

When reaction-path curvature is large, it may be necessary to include excited states of the

product of the exothermic direction in order to obtain accurate results, and the user of

Polyrate is responsible for checking this by checking convergence with respect to the

argument of the EXCITED keyword in the TUNNEL section.

VTST methods are also applicable to state-selected reactants if the quantum number of

the selected mode remains adiabatic, to a good approximation, all the way to the

transition state. Excited-state tunneling probabilities may be defined using similar

methods to those mentioned above, and they are called MEPSA, CD-SCSA, and LC3 or

LC4, i.e., we don't include the G when the method is applied to excited states of reactants.

These abbreviations and the ZCT, SCT, and LCT abbreviations are also useful when we

wish to refer to the semiclassical method without reference to the initial state. The

present version of Polyrate allows the MEPSA and CD-SCSA options for excited-state

reactions but does not allow LC3 or LC4, which is not coded in such generality.

Regions of large reaction-path curvature can promote vibrational nonadiabaticity. The

partial-reaction-path (PRP) adiabaticity approximation [Ref. 13A, Sect 21] assumes

adiabaticity in the excited-state vibration up to the first point along the reaction

coordinate where an appreciable local maximum in the reaction-path curvature occurs,

which we denote s+. The vibration is assumed to relax nonadiabatically into the ground

vibrational state after s+. The adiabatic potential for tunneling is the excited-state one up

to s+ and the ground-state one for s>s+. Excited-state PRP calculations can be

implemented using the STATE and STATEOPT keywords in the RATE section. An

example of an excited-state PRP calculation is provided in test run ohcltr4.

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The multidimensional tunneling methods used in Polyrate have been tested extensively

against accurate quantal results [Ref. 53, Sect 20].

6.E. Reactant and product properties

The first step in the calculation is to determine the properties of the reactants and

products. We will specifically discuss reactant A (the first reactant, which may be an

atom or molecule) as an example in this subsection; the methods for the other reactant, in

the case of a bimolecular reaction, or for products are analogous.

The calculation begins by determining the equilibrium geometry and energy for reactant

A on the potential energy surface. The reactant geometry is optimized by using either the

Newton-Raphson (NR) method with Brent line minimization [Ref. 14, Sect. 22], the

Broyden-Fletcher-Goldfarb-Shanno (BFGS) method [Ref. 15, Sect. 22], or the

Eigenvector Following (EF) method [Refs. 54-58, Sect. 22] to search over a restricted set

of atomic Cartesians coordinates. These options are not available for the program

packages MORATE and AMSOLRATE, in which the geometry optimization is only carried

out in the electronic structure program (which is specified using option HOOK). To do

this, the user must fix (somewhat arbitrarily) 6 of the Cartesian coordinates (5 for a linear

species) and search over the rest. For example, the user might fix atom 1 at the origin,

atom 2 on the x-axis, and the atom 3 in the x-y plane. (In the case of solid-state or gas-

solid-interface reactions, there are no translations or rotations because the moving atoms

are adsorbed on or embedded in a stationary lattice; thus for such cases, the full set of

atomic Cartesians of the movable atoms is used). Starting from an initial guess, an

improved estimate for the position of the minimum is obtained by taking a step ,

where is obtained by solving a simultaneous set of equations (given in the GTST

book chapter) involving the matrix of second derivatives of the potential energy and the

gradient. Once is obtained by direct calculation of the inverse Hessian matrix (NR

method) or estimated using information from the previous geometry optimization steps

(BFGS method), a new guess for the position of the minimum is obtained using either the

NR step or a variable step size which is determined by the Brent line minimization

method [Ref. 16, Sect. 22] (BFGS method). For the EF method, the step is determined

by the hessian. If the hessian has the wrong number of negative eigenvalue, then the

partitioned rational function (P-RFO) approximation is used. If the hessian has one

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negative eigenvalue, then Newton-Raphson step is used. The detailed EF algorithm is

given in [Ref. 56, Sect. 22].

For all methods, convergence is reached when the maximum component of the gradient

in the space of optimized coordinates is less than a prescribed amount GCOMP. In order to

increase the stability of the optimization, the maximum component of the step, DR0 , is

not allowed to be larger than the prescribed amount SCALE for the NR and BFGS

methods. However, the SCALE keyword has no effect on the EF method. The accurate

Hessian is recalculated every HREC optimization steps. In the case of the NR method, if

HREC is not equal to 1, the Hessian is kept frozen until recalculated. The BFGS method is

the default. The EF method has a few extra options, namely, RMAX, RMIN, OMIN, DDMAX,

and DDMAXTS, to control the size of the trust region and tune up the optimization

procedure.

Next, the origin is moved to the center of mass of reactant A. The moment of inertia or

the product of the principal moments of inertia is then determined. Finally, a normal

mode analysis is performed on reactant A. Since, in mass-scaled Cartesians, motion in

any direction is associated with the same reduced mass (that is why we call these

isoinertial coordinates), this is easily accomplished by diagonalizing the force constant

matrix. The force constant matrix is calculated by numerical first derivatives of the

analytic or input first derivatives of the potential. In the case of gas-phase reactions, we

can optionally project out the contamination of the translational and rotational motions in

the force constant matrix at the stationary point before diagonalizing it to yield 6 zero

eigenvalues (5 for a linear molecule) corresponding to overall translation and rotation.

The remaining eigenvalues are all positive, corresponding to bound normal mode

frequencies, and their associated (normalized) eigenvectors Lm give the normal mode

directions. After the frequencies are calculated, the frequencies and corresponding

eigenvectors are placed in “canonical order.” Canonical order is defined as follows:

First define G:

Stationary point: G = R + T = 6 for nonlinear molecule,

5 for linear molecule,

0 for gas-solid interface.

Reaction path: G = R + T + 1

Then the frequencies are ordered as follows:

1. The G frequencies with the smallest absolute values go last, ordered in

order of decreasing magnitude.

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2. Of the remaining frequencies, first put the real ones, in decreasing

order, then put the imaginary ones, in order of increasing magnitude.

By computing or reading the third and fourth derivatives of the potential energy along

these normal mode directions, anharmonicity may be included separately in each of the

modes, as discussed elsewhere [Ref. 1, Sect. 21]. Depending on the method chosen for

treating the anharmonicity, the zero point energy is then computed for reactant A by

summing up the zero point energies in each of the normal modes.

The calculations in this section are then repeated for the other reactant (if it exists) and

for product(s). From these results, the adiabatic energy of reactants, the classical

endoergicity for the reaction, E, and the product adiabatic energy are obtained.

Notice that the normal mode analysis can only be carried in rectilinear coordinates for

reactants and products, whereas the saddle point and the nonstationary points can be

treated either in rectilinear or in curvilinear coordinates. (It is very important to use

curvilinear coordinates rather than Cartesian coordinates for VTST calculations;

Cartesian coordinate will very likely yield imaginary frequencies along the reaction

coordinate, which will cause unphysical VTST results.)

6.F. Saddle point properties

The calculation of the saddle point geometry and properties is next. The saddle point

position is determined by means of the Newton-Raphson method, the BFGS method, or

the EF method as described in Subsection 6.E. The default for transition state searches is

the Newton-Raphson method. This optimization provides the saddle point’s classical

barrier height VMEP (s = 0). Next, the origin is moved to the center of mass of the full N-

atom system. The moment of inertia is obtained as discussed for reactants. Next the

force constant matrix is calculated in mass-scaled Cartesians, and optionally the

contributions of the overall translational and rotational motions are projected out. The

normal mode analysis can be carried out in either the rectilinear or curvilinear

coordinates for the saddle point. (It is very important to use curvilinear coordinates rather

than Cartesian coordinates for VTST calculations; Cartesian coordinate will very likely

yield imaginary frequencies along the reaction coordinate, which will cause unphysical

VTST results.) In the case of using rectilinear coordinates, a diagonalization of the 3N

3N matrix of force constants in mass-scaled Cartesian coordinates is performed. Upon

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diagonalization, we again obtain 6 zero eigenvalues (5 for a linear molecule, 0 for solid

state), 3N-7 (3N-6 or 3N-1) positive eigenvalues corresponding to bound normal mode

frequencies, and one negative eigenvalue corresponding to the imaginary frequency

whose eigenvector provides the reaction coordinate direction at the saddle point. After

the frequencies are calculated, the frequencies and corresponding eigenvectors are placed

in canonical order (which is defined in Section 6.E). The imaginary frequency is used at

a later stage to compute the Wigner tunneling correction (see Subsection 6.J). By

computing or reading the third and fourth derivatives along the normal mode directions

as discussed above, anharmonicity can be included separately in each of the 3N-7 (3N-6

for a linear molecule, or 3N-1 for solid state) bound normal modes (see Subsection 10.B

of this manual), and the zero point energy (ZPE) for the transition state is computed from

the sum of the zero point energies of each of the modes. The ground-state adiabatic

energy at the saddle point is then calculated as:

Va

G s = 0( ) =Va n = 0, s = 0( ) =VMEP(s = 0)+ ZPE(s = 0) (2)

The normal mode analysis can also be carried using redundant (or nonredundant)

curvilinear coordinates. In this case, Wilson’s FG matrix method is used to obtain the

projected force constant matrix in internal coordinates. See Section 10.L. for further

discussion of curvilinear internal coordinates.

6.G. Reaction path

In this section, we discuss how the reaction path (or, more precisely, a set of points along

an approximation to the reaction path) and various properties along it are determined. In

the present version of Polyrate, the reaction path is always taken as the minimum-energy

path (i.e. the path of steepest descents) in mass-scaled coordinates; this is called the MEP.

Note that the path of steepest descent is the same in any isoinertial coordinate system.

[Ref. 49, Sect. 22] There are four cases, and the current version of Polyrate allows three

of them:

In START In PATH

STATUS = 0

SADDLE

Reaction has a saddle point. Initial guess of its

geometry is provided in the START section of the fu5

input file. The geometry of the saddle point is

optimized. The first step is followed along the

imaginary frequency normal mode (if FIRSTSTEP is

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nmode) or with the cubic starting algorithm based on

this mode (if FIRSTSTEP is cubic).

STATUS = 2

SADDLE

This is the same as above except it assumes that the

geometry in the START section is already fully

optimized, and it skips the optimization step.

STATUS = 0 NOSADDLE Not supported.

STATUS = 2

NOSADDLE

Reaction does not have a saddle point. It is a strictly

downhill association reaction. The reaction path is

started by following the negative gradient at the

geometry provided in the START section.

Most of the test runs in the current version of Polyrate correspond to STATUS = 0/SADDLE.

An example of STATUS = 2/SADDLE is test run oh3tr1. All fu29, fu30, fu31, and fu40 test

runs use STATUS = 2/SADDLE. An example of STATUS = 2/NOSADDLE is ho2tr2.

6.G.1. SADDLE option

Taking the saddle point as the first point on the reaction path, an initial step of prescribed

length is taken according to one of two options. Either it is taken based on a cubic

expansion of the potential energy surface [Ref. 17, Sect. 22] using the normalized

eigenvector corresponding to the imaginary frequency and the curvature vector, both of

which are calculated at the saddle point, or it is taken in the direction given solely by the

normalized eigenvector corresponding to the imaginary-frequency normal mode at the

saddle point, as was done in the original version of the program [Ref. 1, Sect. 21]

described in the GTST book chapter.

In the original straight VTST calculations [Ref. 18, Sect. 22; Ref. 1, Sect. 21] the MEP

was calculated by the Euler steepest-descents (ESD) method in which repeated steps of

length s are then taken in the direction of the negative of the normalized gradient. The

whole process is then repeated for the other direction of leaving the saddle point, thus

providing the entire reaction path. The distance between successive points along the

reaction path (s) is called the reaction path stride or the gradient step size, and the set of

such points is called the fine grid or the gradient grid. Thus, at each point on the fine grid

both the potential and gradient are required.

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To reduce the numerical error in the above approach due to wandering about the true

steepest-descent path, the program allows for a stabilization algorithm to be employed.

This algorithm [Ref. 18, Sect. 21] may be considered to be a modified version of the

prescriptions of Ishida et al. [Ref. 19, Sect. 22] and Schmidt et al. [Ref. 20, Sect. 22]. It

is called ES1 (Euler stabilization method, version 1), and it is described elsewhere [Ref.

18, Sect. 22]. In the original version of the ES1 algorithm, the stabilization step was

omitted whenever the vector difference between successive normalized gradients was less

than 10-8, but now this is only a default value and the user is free to choose among other

possible values which might be more appropriate for the reacting system under study.

This is controlled by the keyword DIFFD.

The ES1 method involves two auxiliary parameters, the stabilization step size DELTA2

and the tolerance in the allowed magnitude DIFFD of the vector difference between

successive normalized gradients, and the accuracy achieved for a given amount of

computer time can be sensitive to these values. These values have been approximately

optimized in a systematic study of methods for calculating minimum energy paths (see

Ref. 27 in Sect. 21). In that study, "standard" values were determined for both

parameters. These "standard" values are: a) the stabilization step size DELTA2 equal to

the gradient step size SSTEP, and b) the tolerance in the allowed magnitude of the vector

difference between successive normalized gradients equal to 0.01. When the ES1 method

is used with these choices for the stabilization step size and the tolerance in the allowed

magnitude of the vector difference between successive normalized gradients, the

algorithm is called the optimized ES1 method or ES1*.

The program also allows one to use the Page-McIver algorithm [Ref. 17, Sect. 22], rather

than the ESD or Euler stabilization method, to compute the reaction path. In our

implementation of the Page-McIver method, the first step away from the saddle point is

again taken as described above, and subsequent steps are taken using a local quadratic

approximation (LQA) as described in [Ref. 17, Sect. 22] or in the hard-copy manual for

version 1.5.

Polyrate can also use the variational reaction path algorithm based on the Euler steepest-

descents method, called VRP(ESD) [Ref. 49, Sect. 21], to construct the reaction path.

Methods for calculating the reaction path are discussed further in Sect. 10.D.

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In order to obtain the partition functions needed to evaluate kGT(T, s), a generalized

normal mode analysis is performed at regular intervals along the reaction path. This is

done at the points referred to as the save grid. The generalized normal mode analysis

can be carried out in either rectilinear (Cartesian) or curvilinear coordinates. (It is very

important to use curvilinear coordinates rather than Cartesian coordinates for VTST

calculations; Cartesian coordinate will very likely yield imaginary frequencies along the

reaction coordinate, which will cause unphysical VTST results.)

The algorithm used for rectilinear coordinate calculations is discussed by Miller, Handy,

and Adams [Ref. 7, Sect. 22]. In particular, for s 0 the rectilinear or Cartesian

generalized normal modes orthogonal to the reaction path are obtained from the projected

force constant matrix

 

FP s( ) = 1-P s( )[ ]F s( ) 1-P s( )[ ] , (3)

where F(s) is the full (3N 3N) Cartesian force constant matrix evaluated at a point on

the MEP, and [1 - P(s)] is a projector used to project the direction along the reaction path

as well as overall rotations and translations out of the space associated with the non zero

eigenvalues. Diagonalization of FP(s) gives 7 zero and 3N–7 positive eigenvalues (6 zero

and 3N–6 positive eigenvalues for linear molecules, or 1 zero and 3N–1 positive

eigenvalues for adsorbed species) corresponding to the bound generalized normal modes

orthogonal to the reaction coordinate. After the frequencies are calculated, the

frequencies and corresponding eigenvectors are placed in canonical order (which is

defined in Section 6.E). If the REORDER keyword is specified, the code will attempt to

correlate the modes from point to point in terms of their physical characters rather than

their magnitudes. Thus the first mode would be the mode with the highest overlap with

the first mode at the previous point, rather than the highest-frequency mode, and so forth.

The REORDER option would be useful for studying diabatic correlations of vibrational

modes. Once the frequencies have been reordered anharmonicity corrections, the zero

point energy, and the ground-state adiabatic energy are computed as they were at the

saddle point.

The curvilinear generalized normal mode analysis is carried out by first transforming the

Cartesian force constant matrix into a curvilinear coordinate system, then projecting out

the gradient components, and finally diagonalizing the projected curvilinear force

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constant matrix according to Wilson GF method [Refs. 36 and 37 of Sect. 22] as

described in Refs. 41, 43, 45, and 46 of Sect. 21. Generalized normal mode frequencies,

the zero point energy, and the ground-state adiabatic energy are then computed as they

were at the saddle point. Methods for calculating the curvilinear generalized normal

mode frequencies are discussed further in Sect. 10.M.

Section 10 and the GTST book chapter give details of the WKB method for computing

anharmonic vibrational energies.

Starting with Polyrate version 4.0, vibrational modes corresponding to torsional motion

can be treated with the hindered-internal-rotator approximation [Refs. 24, 29, and 34,

Sect. 21].

6.G.2. NOSADDLE option

The NOSADDLE option is used only for strictly downhill association reactions. It requires

the user to input an initial guess for a point on the MEP such that the variational

transition state lies between this point and the product, which is the associated molecule.

Let s = 0 denote the initial guess, and let

 

sP denote the value of s at the product.

Typically, one will compute the MEP only up to some value

 

s2 that is less than

 

sP.

Furthermore, the first few points are typically not useful because it takes a few steps for

the path generated by the steepest descent algorithm to become sufficiently close to the

MEP. If this occurs by

 

s = s1, where

 

0 £ s1 £ s2, then it is the user’s responsibility to

ensure that the variational transition state lies between

 

s1 and

 

s2.

Starting with Polyrate version 2008, VRC option is recommended instead of NOSADDLE

option for barrierless association reactions. The VRC option uses a variable reaction

coordinate and single-faceted or multifaceted dividing surfaces. See Sections 11 and 13

for details.

6.H. Reaction-path curvature

The curvature of the reaction path is used in both the SCT and LCT calculations. The

curvature of the reaction path is a vector with F – 1 components, where F is the number

of internal degrees of freedom (F = 3N – 6 for a gas-phase reaction with a nonlinear

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reaction path, F = 3N – 5 for a gas-phase reaction with a linear reaction path, and F = 3N

for a solid-state reaction employing a fixed lattice, as in the embedded-cluster method).

In this manual the components of the curvature vector are denoted BmF, m = 1,2, ...,F-1,

where m labels a generalized-normal-mode direction.

When using an analytic potential energy surface or electronic structure input data from

unit fu30 or unit fu40, there are three choices for how to compute BmF. The first two

choices are based on eq. (98) of the GTST book chapter [Ref. 5, Sect. 21]. This formula

involves a numerical derivative of the negative gradient, and this derivative may be

computed by central or one-sided finite differences. The third choice is to use eq. (48) of

a paper by Page and McIver [Ref. 17, Sect. 22]. Notice that eq. (98) of the GTST book

chapter is the same as eq. (47) of Page and McIver paper. An advantage of eq. (48) is

that it does not involve numerical differentiation of the gradient. Both formulas require

the generalized-normal-mode eigenvectors so the curvature is calculated on the Hessian

grid (as opposed to the gradient grid). The evaluation of the curvature by taking the

derivative of a quadratic fit to the gradient at three points (i.e., a central finite difference)

is specified by the option dgrad of the keyword CURV; the evaluation by taking the

derivative of a one-sided two-point fit to the gradient is called oneside, and the

evaluation by eq. (48) of Page and McIver is called dhess because it involves a

derivative of the Hessian. Although in principle, dhess can be used even when the

reaction path is calculated by the ESD method, this can be dangerous because the

accuracy of a numerical derivative requires a small step size. When the ESD method is

used to calculate the reaction path, the gradient may be known on a much finer grid than

the Hessian grid, and numerical differentiation of the Hessian may be inaccurate. If the

dhess option is used with an ESD integration scheme, one should be especially careful

to converge the Hessian with respect to INH.

These methods all break down (become unstable) at or very near to the saddle point.

Thus the code does not obtain the curvature vector directly at the saddle point. Instead it

obtains the value of BmF at the saddle point by linear interpolation of the absolute values

at the closest negative-s save grid point and the closest positive-s save grid point. That is,

if the saddle point is sNS , one obtains the curvature at the saddle point as an average of

the values at

 

sNS-1 and

 

sNS+1 if INTMU equals 1, and one obtains the curvature at the

saddle point as an average of the values at

 

sNS-2 and

 

sNS+2 if INTMU equals 3. The

curvature at the saddle point is used to calculate

 

meff (s) at sNS . There is an option to

compute

 

meff (s) at

 

sNS,

 

sNS-1, and

 

sNS+1 by linear interpolation of the values at

 

sNS-2

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and

 

sNS+2. This option is corresponds to setting INTMU equal to 3 in the PATH section,

this is currently the default.

When using the electronic structure data from unit fu31, the method for computing BmF

is automatically chosen based on whether or not a gradient is available at the closest point

on both sides of the Hessian point. If gradients are available on both sides of the point

then the three gradients are fit to a quadratic function and the derivative of this function is

calculated and then evaluated at the Hessian grid point. If the gradient is only available

on one side then the derivative is evaluated by one-sided difference. For obtaining the

curvature vector at the saddle point the procedure described above is also used.

However, if the user selects to perform a direct interpolation of the exponent in eq. 10 of

Ref. 48 in Sect. 21, the IVTST-M calculation will obtain eff at the saddle point from a

spline fitting of the exponent as a function of the mapping variable z. See Section 6.N.2

for more IVTST-M details.

In contrast, when data is obtained from unit fu29, which is used for IVTST-1

calculations, the curvature at the saddle point is computed using an alternative formula

presented as equation (49) in the Page and McIver article [Ref. 17 of Sect. 22], and its

value at the "extra point" is computed again using eq. (48) of the same reference. The

value at the saddle point is actually used in the IVTST-1 calculation, whereas the value at

the extra point is computed for informational purposes only.

See Section 10.F for further discussion of the curvature calculations.

6.I. Transmission coefficients

The temperature-dependent ground-state transmission coefficient is the ratio of the

Boltzmann average of the quantum energy-dependent ground-state transmission

probability to the Boltzmann average of the energy-dependent transmission probability

corresponding to classical-reaction-coordinate motion with other degrees of freedom in

the ground state. Both transmission probabilities are zero for an energy lower than the

maximum of the ground-state energy of the reactants and of the products. For VT, the

threshold energy for the classical transmission probability is the maximum of the

adiabatic ground-state energy

 

VaG s( ) , i.e.,

 

VaAG ; it is

 

VaG s = 0( ) for TST and

 

VaG s = s*

CVT( ) for CVT. One can factor the ground-state transmission coefficient into

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two factors. The first factor is a ratio of the Boltzmann average of the quantum

transmission probability to the Boltzmann average of the classical transmission

probability with the threshold energy at the maximum of the adiabatic ground-state

energy. The second factor is a ratio of the Boltzmann average of the classical

transmission probability with the threshold energy at the maximum of the adiabatic

ground-state energy to the Boltzmann average of the classical transmission probability

with the threshold at the value that is consistent with the level of variational theory being

applied. In the FORTRAN unit fu6 output, the first factor is denoted as ZCT, SCT,

LCG3, LCG4 and the second factor is denoted as TST/CAG and CVT/CAG for the TST

and CVT levels of theory, respectively. Since this CAG factor is exactly 1 in the case of

VT, it is not listed in the output. The final result is denoted as, e.g., CVT/ZCT for a

transmission coefficient evaluated with the ZCT (or MEPSAG) method at the CVT level.

The CAG factor is required for consistency in TST and CVT calculations (but not in VT

calculations), although it is often close to unity. The CAG correction was introduced in

Refs. 10 and 44 of Sect. 22, and the reader is referred to those references for further

discussion.

The MEPSAG, CD-SCSAG, and LCG3 or LCG4 transmission coefficients are simply

denoted ZCT, SCT, and LCT, respectively, in recent papers, as discussed in Section 6.D

above. The ZCT method should be considered simply as an approximation to SCT to be

used when insufficient information is available to compute the reaction-path curvature.

The SCT transmission coefficient is always larger than (or equal to) the ZCT one. The

SCT transmission coefficient is expected to be larger than and more accurate than the

LCT one when reaction-path curvature is small over the classically forbidden segment of

the reaction path; the LCT transmission coefficient is expected to be larger than and more

accurate than the SCT one when reaction-path curvature is large in the classically

forbidden section of the VaG(s) curve. These two situations are discussed in more detail

in discussion remarks at Faraday Symposium 29 on Potential Energy Surfaces and

Organic Reaction Paths [Ref. 45 in Sect. 22], and they are illustrated (in color) in an

earlier review article [Ref. 46 in Sect. 22].

Whenever there is enough information available to calculate LCT transmission

coefficients there is also enough data available to calculate SCT ones (although the

converse is not true). In such cases the recommended best estimate is obtained by the

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microcanonical optimized multidimensional tunneling (µOMT) approximation that is

discussed in Section 6.M.2 below.

The optimized multidimensional tunneling approximations are reviewed below. In

particular, Subsection 6.M.1 reviews the canonical optimized multidimensional tunneling

(COMT) method, and Subsection 6.M.2 discusses the microcanonical optimized

multidimensional tunneling method (µOMT).

6.J. Reaction rates including tunneling

In this subsection, we describe the calculation of the reaction rate constants as discussed

in Subsection 6.A.

For a given temperature T, various transmission coefficients (T) are computed using

methods selected by the user, all of which lead to different approximations to the rates.

Next, the s-independent quantities are determined, i.e., the electronic, translational,

rotational, and vibrational partition functions for reactant(s) and product(s), as well as the

electronic partition function for the generalized transition state and the prefactor for the

rate constant.

Next, for each s at which a generalized normal mode analysis was performed the program

computes the rotational and vibrational partition functions of the generalized transition

state to get the generalized free energy of activation at this value of s. Using the nearest

points to the maximum, parabolic and quartic fits are used to obtain the interpolated

maximum of . The final location and generalized free energy of activation

at this maximum are obtained from the quartic fit (the parabolic fit is just for

comparison).

The calculation of the kappa factors is described next. The Wigner tunneling correction

for conventional TST is also computed, but only for informational purposes. It is not a

recommended method because it is just the first two terms in a slowly convergent or

divergent series. For thermal reaction rates, the MEPSAG, CD-SCSAG, and LCG3 or

LCG4 transmission probabilities are averaged over a thermal distribution and divided by

the thermal average of the classical transmission probabilities. As mentioned previously,

CD-SCSAG, LCG3, and LCG4 methods take into account the coupling between the

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reaction path curvature and the vibrational modes. In this version of POLYRATE, the

LCG3, LCG4, and CD-SCSAG methods treat vibrational modes harmonically. (The

current version of the program will not perform LCG3 or LCG4 calculations if

anharmonic options other than the hindered-rotator method are selected. In the case of

CD-SCSAG, zero-point energies and vibrational partition functions can be treated using

one of the various anharmonicity methods, and the CD-SCSAG kappa factor will change

due to the change in the adiabatic ground state potential. However, the CD-SCSAG

method is still based on a harmonic approximation.) The procedures for calculating the

transmission probabilities and transmission coefficients for the MEPSAG method are

described completely in the GTST book chapter, and the description of the CD-SCSAG

method can be found in Refs. 29 and 31 of Sect. 21. For the LCG3 or LCG4 calculation

the basic idea is in the GTST book chapter and additional details of the implementation

are described in Refs. 21, 29, 31, and 34 of Sect. 21. (Note that the value of s along an

LCG3 or LCG4 tunneling path is a continuous function of progress along the path, as

described correctly in the GTST book chapter and not as described in Ref. 21 of Sect.

21.)

Early versions of Polyrate used a method called SCSAG. This has now been replaced by

CD-SCSAG. The two methods are identical if the reaction-path curvature has only one

nonzero component; otherwise they differ, and CD-SCSAG is based on a more correct

analysis of the geometry of corner-cutting tunneling.

In the Polyrate program, the Kronrod quadrature for MEPSAG and CD-SCSAG

tunneling calculations is performed using the independent variable s and abscissa gi

rather than y and yi; see page 99 of the GTST book chapter.

Furthermore, for both the (E) integral over s, eq. (94), and the Boltzmann average, eq.

(91) of the GTST book chapter, the range of integration is divided into 1-3 equal

segments, and the same order of Kronrod quadrature is used in each. For the (E)

integral we use NSEG2 segments with (2*NQTH+1)-point Kronrod quadrature in each, and

for the Boltzmann integral we use NSEG segments with (2*NQE+1)-point Kronrod

quadrature in each. Kronrod's method provides NQTH-point and NQE-point Gauss-

Legendre quadrature results as well. It is important to check the convergence of these

integrals by comparing the N-point and (2N+1)-point results.

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The CD-SCSAG and LCG3 or LCG4 transmission probabilities are also used to calculate

optimized multidimensional tunneling approximations called COMT and OMT, as

discussed in Sections 6.M.1 and 6.M.2.

Using the various generalized transition state approximations and k (T) factors, various

forward and reverse rate constants at temperature T can be obtained, e.g., the combination

of an CVT rate constant with an MEPSAG tunneling correction yields an CVT/MEPSAG

rate constant.

If the VTST-IOC correction is selected, the program updates all the energy, frequency,

and determinant of moment of inertia information to the corrected values and recalculates

the tunneling probabilities. A new set of corrected rate constants is then obtained.

If the VTST-ISPE correction is selected, the program spline fits the differences of the

lower-level energies and the higher-level energies using the IVTST-M algorithm. The

interpolated values are then added on to the lower-level and a new set of corrected rate

constants is obtained. See Section 10.J for a detailed description.

6.K. Imaginary-frequency modes transverse to the reaction path

When a generalized normal mode eigenvalue is negative, i.e., the harmonic frequency of

a mode transverse to the reaction path is imaginary (recall that the eigenvalues are

squares of the frequencies), the program takes the following actions:

1. When an independent-normal mode method is being used, the vibrational

partition function of that mode is set equal to 1.0 1010.

2. The zero-point energy of that mode, as required for the calculation of the

vibrationally adiabatic ground-state potential curve for tunneling calculations,

is set equal to zero.

3. The turning point distance of that mode is set equal to 1.0 1010 bohr for the

LCG3 or LCG4 calculations.

4. For the CD-SCSAG method, no contribution from this mode is included

whether the harmonic or anharmonic approximation is selected.

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6.L. Equilibrium constant calculation

In the current version of the code this calculation is the last to be performed. However,

the calculation is carried out in two different subroutines, TSOUT and FINOUT. If a TST-

only calculation is requested, then all the rate calculations are carried out in the

subprogram TSRATE, which calls TSOUT. TSOUT prints the rate constants to the fu6 file

and the fu15 (summary) file, and it calculates and prints the equilibrium constants using

the TST rate constants.

The subprogram RATE, which calls FINOUT, calculates the rate constants with canonical

variational theory (CVT). FINOUT computes and prints final rate constants, activation

energies, and equilibrium constants (from the CVT rate constants).

In both cases the equilibrium constants are the last quantities calculated in the respective

subprograms.

6.M. Omitting the product

Polyrate can be run without calculations on the product if reverse rate constants

and equilibrium constants are not calculated. This requires specifying the FORWARDK

keyword in the RATE section of the fu5 input.

What the code will do then depends on whether there is a WELLP section in the

fu5 input. If there is a WELLP section, the interpolation extends to the product-side well

as described at Section 3.1 of Ref. 48 of Sect. 21. If there is not a WELLP section, then

the interpolation extends to the last nonstationary point on the product side. Thus

VMEP(s) is cut off (down to the product value) at that point, and if tunneling extends into

the region beyond the last nonstationary point on the product side, it will be

overestimated.

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6.N. Optimized multidimensional tunneling calculations

6.N.1. COMT method

The canonical optimized multidimensional tunneling (COMT) temperature-dependent

transmission coefficient is the larger of the thermally averaged temperature-dependent

transmission coefficients calculated by the CD-SCSAG method and the LCG3 or LCG4

method at a given temperature. The COMT method was first used in Ref. 28 of Sect. 21

(where it was simply called MT). It was first called COMT in Ref. 34 of Sect. 21.

6.N.2. µOMT method

The microcanonical optimized multidimensional tunneling (µOMT) temperature-

dependent transmission coefficient is the ratio of the Boltzmann average of the µOMT

quantum transmission probability to the Boltzmann average of the classical transmission

probability, where the µOMT quantum transmission probability is the larger of the

energy-dependent transmission probabilities evaluated by the CD-SCSAG method and

the LCG3 or LCG4 method at a given energy. This method was introduced in Ref. 34 of

Sect. 21. See Also Ref. 45 in Sect. 22.

6.O. Interpolated VTST and mapped interpolation

Calculating

 

VMEP(s), |I(s)|, and

 

w(s) as needed for variational transition-state theory

and tunneling calculations from ab initio electronic structure theory can be

computationally demanding. Thus, it is sometimes desirable to interpolate these

quantities based on electronic structure data only at the reactant, product, saddle point,

and optionally a small number of additional points (close to the saddle point) along the

MEP. Variational transition-state theory based on interpolated data at a few points on the

MEP [Ref. 43 in Sect. 22 and Refs. 26, 32, and 48 in Sect. 21] is called interpolated

VTST or IVTST.

Three implementations of IVTST are included in this version of the Polyrate program.

The first is zero-order IVTST (IVTST-0) and the second is first-order IVTST (IVTST-1)

using the global interpolation approach. The third is IVTST-M which is described in

Section 6.O.2 and 6.O.3. Permutation of frequencies is not included in any of these

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methods. TST rates and ZCT transmission coefficients can be calculated with IVTST-0;

in addition CVT rates and SCT transmission coefficients can be calculated with IVTST-

1. Moreover, IVTST-M may be used for TST, CVT, VT, and CUS rates and ZCT and

SCT transmission coefficient calculations.

6.O.1. IVTST-0 and IVTST-1

IVTST-0 and IVTST-1 calculations [Ref. 26, Sect. 21] can be performed for bimolecular

reactions by using the IVTST0 or IVTST1 keywords in the GENERAL section. Alternatively,

IVTST-0 calculations can be performed using file fu50. Presently IVTST-0 and IVTST-

1 methods are only available for bimolecular reactions with two reactants and two

products.

The IVTST-0 method assumes that information is only available at three locations on the

potential energy surface, namely at the reactant (R), saddle point, and product (P).

Details of the interpolation procedures can be found in Ref. 26 of Sect. 21. The IVTST-0

rate constant is the conventional TST rate constant with ZCT tunneling. Note that ZCT

tunneling is the only available tunneling method for IVTST-0. ZCT tunneling

calculations for zero-order IVTST are carried out using

 

VaG (s) = VMEP + ZPE(s),

where

 

VMEP(s) is represented by an Eckart function and ZPE(s) is obtained from

interpolated values.

The IVTST-1 method requires information for one extra point (

 

s = s1) near the saddle

point in addition to the saddle point, R, and P. The

 

VMEP(s) curve for the IVTST-1

calculation is also approximated by an Eckart function with a constraint that the Eckart

function goes through the extra point at

 

s = s1. To determine the location of the

variational transition state, the forward standard-state free energy of activation profile,

is calculated using the interpolated

 

VMEP(s),

 

I(s) , and

 

w(s). The SCT

transmission coefficients can be obtained for first-order IVTST using the interpolated

 

meff (s).

IVTST-0 calculations can also be performed by using the keyword ICOPT in the GENERAL

section and the keyword 0IVTST in the unit fu50 input (see Subsection 12.F). In the

current version, this method is available only for bimolecular reactions with two

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products, and therefore the keywords MEPTYPER and MEPTYPEP for the unit fu50 input

should both be set to 2. In addition, the keywords MEPTYPER and MEPTYPEP should not be

set to well, and the keyword FREQMAT should not be used. The hindered rotor

approximation is currently the only anharmonicity option that can be used with IVTST-0

when using file unit fu50 for the IVTST-0 calculation. At this time there are no

anharmonicity options for IVTST-0 nor IVTST-1 calculations when using file unit fu29.

For the IVTST-0 calculations, only conventional transition state theory rate constants and

ZCT transmission coefficients can be calculated. Variational transition state theory at the

CVT level and both ZCT and small-curvature tunneling (SCT) transmission coefficients

can be obtained for IVTST-1. Details can be found in Ref. 26 of Sect. 21.

6.O.2. Interpolated VTST by mapping (IVTST-M)

IVTST-M is a method for obtaining the information required for a VTST calculation all

along the reaction-path from the information available at a small number of points. The

only limitations on using the IVTST-M algorithm are that a saddle point exists and

reaction path information is available for least one nonstationary point on each side of the

saddle point. In addition, as in all IVTST methods, information is required for 3 – 5

stationary points (reactants, saddle point, products, and optionally one or two wells). The

level of IVTST-M is denoted by two numbers, H and G, indicating respectively the

number of nonstationary points at which Hessians are available and the number of

nonstationary points at which gradients are available. Thus, IVTST-M-6/54 indicates that

the interpolation is based in 6 nonstationary Hessian points, at which geometries,

energies, gradients, and Hessians are available, and 48 points (which is 54 minus 6) for

which only geometries, energies, and gradients are available. The mapping procedure

transforms VMEP(s), |I|(s), (s), and Bm,F(s) from functions of s into functions of z where

z is a new variable which always has a finite value, whereas s can have infinite values if

either forward or reverse reaction is bimolecular. The parameter z is determined as

 

z = 2p

arctans - s0

L

æ

è ç

ö

ø ÷ , (1)

with s0 and L being two parameters obtained from the forward and reverse barrier heights

[Ref. 48 in Sect. 21].

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The new VMEP(z), |I|(z), (z), and Bm,F(z) functions are interpolated by using splines

under tension.

The method employs different approaches for the interpolation of VMEP(s), depending on

the number of reactants and products in the reaction. If the reaction is unimolecular in

either the forward or reverse direction, a cubic polynomial for estimating 10 energies

between the reactant (or product) and the first (or last) point on the reaction path (or

between the reactant and the first point and between the product and the last point) is

calculated before carrying out the spline under tension fit. The cubic polynomial can be

function of either s or z. The user should base the choice of s or z on experience or should

test the two choices (using function of s or z) to see which one gives reasonable potential

energy curve. The user can also choose not to use the polynomial to generate the 10 extra

energies; however, the default is to generate them by using a cubic polynomial function

of z. If the forward reaction is bimolecular, the interpolation on the reactant side of the

saddle point is based on the energies from the input plus 10 additional energies estimated

from an Eckart polynomial with a range parameter which is a function of s. Similar

considerations apply on the product side if there are two products.

If for a bimolecular reaction or a reaction with two products, there are wells on the

reactant and/or product side, the interpolation can be done using the information on these

stationary points with the unimolecular procedures, which at least in principle can make

the interpolation more accurate, especially when the well is deep and/or close to the

saddle point. But if a well is present, it can also be ignored, and the interpolation can be

carried out using reactants and/or products. If the well is ignored, then since for

bimolecular reactions (or bimolecular sides of the reaction path) the interpolation is based

on an Eckart potential, no point on the reactant side of the reaction path can be used that

has an energy lower than the reactants energy, and no point on the product side can be

used that is more stable than the products.

The IVTST-M algorithm has been implemented to be used with the hooks and the

electronic structure input files, unit fu30, fu31, and fu40. The method is fully operational

when using the hooks and the unit fu31 input file. When using units fu30 and fu40, only

the IVTST-M default options are available. To use the IVTST-M algorithm with unit

fu30, LOPT(2) must be set equal to –1; and with fu40, MAXLPTS must be set equal to –1.

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Whenever IVTST-M calls TSPACK for a spline-under-tension fit, it sets the variable

IENDL equal to 3. This means that the two extra pieces of data needed for the spline fit

are generated by the ENDSLP subroutine using a local spline under tension.

6.O.3. The mapped interpolation (MI) algorithm with the hooks

As mentioned in Section 1 of this manual, the mapped interpolation (MI) algorithm can

be used in two ways by POLYRATE. The first way is to perform IVTST-M calculations

using electronic structure input file fu30, fu40, or fu31. This method is described fully in

Sections 6.N.2, 10.J, and 11.D of this manual. The second way is in conjunction with the

hooks; this requires some additional comments, which are given in the rest of this section.

A calculation with the hooks involves two stages. At the end of the first stage, one has

stored s, VMEP(s), and the gradients on the fine grid and s, VMEP(s), (s), BmF (s), and

( )I s are stored on the save grid. (The grids are defined in Sect. 7.A) Both grids extend

from s = SLM on the reactant side to s = SLP on the product side, and there are G + 1

points (including the saddle point but excluding reactants and products) on the fine grid

and H + 1 points (including the saddle point but excluding reactants and products) on the

save grid. Then mapped interpolation is carried out to add EXNSTEP * EXSTEP points on

each side of the grids. Furthermore SLM is replaced by SLM – EXNSTEP * EXSTEP, and SLP

is replaced by SLP + EXNSTEP * EXSTEP. As should be clear from Section 12.A.7,

EXNSTEP and EXSTEP may actually be different on the two sides.

6.P. Interpolated optimized corrections (VTST-IOC), a form of dual-level VTST

In VTST calculations with approximate potential energy surfaces, it is sometimes

desirable to correct the classical energies, vibrational frequencies, and moment-of-inertia

determinants of some points along the MEP (e.g., the reactant, saddle point, product, van

der Waals complex, ion-molecule complex, etc.) with accurate (higher-level) results. This

is accomplished by applying correction procedures to the calculated energy, frequencies,

and moment-of-inertia determinant along the MEP. The corrections are calibrated such

that the corrected results match the accurate values at those selected points, and they

correspond to interpolating these corrections at other points. When the corrections

involve data from higher-level optimizations of the stationary points, the method is called

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VTST-IOC, a special case of VTST-IC. The original correction procedure for

frequencies is denoted ICA, and two improved procedures are denoted ICR and ICL. (In

general we recommend the ICL procedure.) The ICA procedure was introduced in

version 5.1 of POLYRATE, and the ICL and ICR procedures were introduced in version 7.0.

All three procedures are based on the correction at 3 points, in particular, the saddle point

and two stationary points, one on each side of MEP.

There are also two procedures for correcting VMEP(s) in IOC calculations: the original

method, which was called NOECKART in versions 7.2 – 7.9.2 of Polyrate but now is called

the single-Eckart (SECKART) method of interpolating VMEP, and the newer method, which

was called ECKART in versions 7.2 – 7.9.2 but now is called double-Eckart (DECKART).

The ECKART option was introduced in version 7.2. As implied by the names of the

correction, is either a single Eckart function or a difference of two Eckart terms. If there

is an appreciable well on either side of MEP, it is recommended that one use the

molecular complex corresponding to the well as the stationary point on that side of the

saddle point; otherwise it is recommended that one use the reactant or the product.

However, if the well on the MEP is not very deep or if accurate data for the complex

corresponding to the well are not available, the user can neglect the well and choose an

appropriate functional form for the correction function as if there were no well at all.

As discussed in Section 1, the VTST-IOC method can be used either with an analytic

potential energy surface or with electronic structure input data for the lower-level surface.

In either case, the information calculated from the potential energy surface or read from

the electronic structure input file will be corrected by the higher-level values.

The functional forms we use for the correction functions are an Eckart function, a

hyperbolic tangent, a cut-off Gaussian, or a cut-off hyperbolic tangent, depending on the

shape of MEP under consideration and the relative correction values at the 3 stationary

points. See Refs. 36 and 44 of Sect. 21 for details. Details for the ICA procedure are

available in Subsection 10.H and in Ref. 36 of Sect. 21 and details for the ICR and ICL

procedures are available in Subsection 10.H and in Ref. 44 of Sect. 21. Details of the

double Eckart procedure are available in Ref. 44 of Sect. 21.

If the higher-level data is obtained at electronic structure level X, and the lower-level data

is obtained at level Y, the VTST-IOC calculation may be denoted X///Y. The triple slash

notation is similar to the double slash notation that is widely used in electronic structure

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calculations. In particular, // means “at a stationary point geometry optimized by...”

whereas /// is loosely translated as “along a reaction path calculated by...”. More

specifically, though, we reserve the IOC and triple slash notations for algorithms were the

higher-level information supplied to “correct” the transition state data involves a higher-

level geometry optimization. If only single-point energies are used, the ISPE and double

slash notation should be used.

6.Q. Interpolated algorithm for large-curvature tunneling calculations

In LCT calculations, for each energy, a tunneling path is defined as a straight line in

isoinertial coordinates between two reaction-coordinate turning points lying on the MEP,

on the reactant side and on the product side of the maximum of the vibrationally adiabatic

potential. This straight-line is divided into three zones, two of them are in the reactant

and product valleys, respectively, and they are vibrationally adiabatic, and another zone

describes the middle zone of the straight-line path and is vibrationally nonadiabatic. In

the interpolated LCT (or ILCT) algorithm, every time the potential energy is needed

along the nonadiabatic segment of the tunneling path, this energy is calculated by means

of the spline fit to a number of already calculated points. Details of the methods are

available in Ref. 55 of Sect. 21.

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7. PROGRAM STRUCTURE

7.A. Overview of program flow

As mentioned in the Introduction, the Polyrate program has several possible ways to

obtain the reaction-path information necessary for rate constant calculations. The first

option is to calculate this information directly from a set of interface subprograms called

hooks. The second is to read this information from an electronic structure input file

(fu30, fu31, or fu40) consisting of geometries, gradients, Hessians, etc. at points on the

MEP obtained from electronic structure calculations. The third option is to read the

information from a restart file which has been saved from a previous Polyrate run. The

fourth option is to read in higher-level “corrections” at selected points along the MEP;

these corrections are read from file fu50 for VTST-IOC and from file fu51 for VTST-

ISPE. Finally, for the IVTST calculations, electronic structure data at selected points

may be read from file fu29 (IVTST-0 and IVTST-1) or fu50 (IVTST-0). These options

are implemented in the Polyrate program as follows.

First, the MAIN program reads all the keyword input. These keywords are analyzed for

possible conflicts (i.e., unsupported combinations of options) in subroutine OPTION. If it

is a restart run then the program reads in the restart information in RESTOR, and the rate

constant calculation proceeds as described in the last paragraph of this section.

Otherwise, all other input data from unit fu5 are read in and checked by READ5 and

REDGEO.

The GENERAL section of keyword input (Section 12.A.2) is always read first. Depending

on the options chosen the properties of the reactants, products, and generalized transition

states are calculated by calls to the hooks or read in from an electronic structure input file

(or both). The user can choose at most one of the two switch keywords IVTST0 and

IVTST1, or use the DL keyword. This choice plus the choice made for the POTENTIAL

keyword in the ENERGETICS section (Section 12.A.3) determines the basic outline of the

rest of the calculations as indicated in the following table. That table assumes that the

hooks call SURF and SETUP, which is the standard way to use the hooks when Polyrate is

used as a stand-alone code. (Subprograms SURF and SETUP are described in Subsection

8.C, and a more complete description of the hooks is provided in the rest of Section 8).

In the present version of the code, user can also turn on the VRC option, which is off by

default, to calculate rate for barrierless association reactions using a variable reaction

coordinate and multifaceted dividing surfaces. When VRC is turned on, potential energies

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can only be calculated through hooks since the Monte Carlo method is used for the

variable-reaction-coordinate calculations with single-faceted or multifaceted dividing

surfaces. Gradient and Hessian are not required for all Monte Carlo samples.

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DL IVTST0 IVTST1 POTENTIAL Action

None off Off hooks Single-level calculation

based on whole reaction

path calculated from an

analytic PES.

none off Off unit30, unit31, or unit40

Single-level direct

dynamics based on

whole reaction path

calculated from an

electronic structure input

file on unit fu30, fu31, or

fu40

none on Off unit29 or unit50

Single-level direct

dynamics IVTST-0

calculation based on

electronic structure input

data from unit fu29 or

fu50

none off On unit29 Single-level direct

dynamics IVTST-1

calculation based on

electronic structure input

data from unit fu29.

ic off Off hooks Dual-level direct

dynamics with lower-

level data from analytic

PES and higher-level

data from unit fu50

ic off Off unit30, unit31, or unit40

Dual-level direct

dynamics with lower-

level data from unit

fu30, fu31, or fu40 and

higher-level data from

unit fu50

ispe off Off hooks Dual-level direct

dynamics with lower-

level data from analytic

PES and higher-level

data from unit fu51

ispe off Off unit30, unit31, or unit40

Dual-level direct

dynamics with lower-

level data from unit

fu30, fu31, or fu40 and

higher-level data from

unit fu51

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In the analytic potential energy surface case, the equilibrium geometries and properties of

the reactant and product species are optionally obtained in subroutine REACT. For

polyatomic species, REACT calls POLYAT, and the user must supply an estimate of the

equilibrium geometry. POLYAT calls NEWT to perform a Newton-Raphson search for the

location where the first derivatives of V are zero, CENTER to place the origin at this

location and evaluate the determinant of the moment of inertia tensor, and NORMOD to do

a vibrational analysis. The vibrational analysis involves determining the normal mode

eigenvectors and frequencies, and, if desired, one of several procedures for including

anharmonicity is invoked in ANHARM. If a diatomic species is treated as a Morse

oscillator (DIATOM keyword) REACT calls DIATOM, and the equilibrium geometry,

dissociation energy, and range parameter must be supplied by the user.

Next, if using he RP-VTST option without NOSADDLE, the program will determine the

saddle point geometry and properties for the tight transition state. This is done in SADDLE

and MAIN, which in turn call the same subroutines used by POLYAT. The program will

handle 0 or 1 saddle points. For one saddle point the user must supply an approximate

geometry for its location. For 0 saddle point, user can choose NOSADDLE option, which

requires the user to input an initial guess for a point on the MEP such that the variational

transition state lies between this point and the product. However, rather than using

NOSADDLE, the VRC option in GENERAL section is recommended for barrierless

association reactions, and this option does not require to input any geometry for transition

state.

When using the hooks, Polyrate starts either at the saddle point just determined or from

an input starting-point geometry, then computes the minimum energy path (MEP) by a

choice of several methods (done in the PATH section of file fu5). The distance along the

MEP is called s; the user can make s be zero at the saddle point, negative in the reactant

region, and positive in the product region. The initial step can be based on a cubic

expansion of the potential energy surface determined from the normalized eigenvector of

the imaginary-frequency normal mode and from the curvature vector, both of which are

calculated at the saddle point, or the initial step may be taken along the normal coordinate

for the unbound motion at the starting point. When the default ESD method is used (RPM

keyword set equal to esd), the negative of the gradient in isoinertial coordinates is

followed using a fixed gradient step size DEL (specified by the SSTEP keyword). At

regular intervals (specified by the INH keyword) along the MEP, the program computes

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the generalized-transition-state properties necessary to evaluate the generalized free

energy of activation and to perform semiclassical tunneling corrections. (We emphasize

that both DEL and the regular intervals are measured in the isoinertial coordinates. Thus

the units are sometimes called mass-scaled angstroms instead of angstroms. Thus if

REDM, specified by the SCALEMASS keyword which is described in Subsection 12.A, is

changed, DEL and the regular intervals will have different meanings.) Note that the grid

determined by DEL is called the fine grid or the gradient grid. The grid defined by the INH

keyword is called the save grid or Hessian grid. This is discussed further in Subsection

10.D. The moment of inertia calculation and Miller-Handy-Adams projections (eq. 31 of

Ref. 5) or curvilinear-reaction-coordinate projections (eq. 17 of Ref. 41) are carried out in

PROJCT; the vibrational analysis and the calculation of the effective mass for tunneling are

done in NORMOD. In addition, if there is a saddle point the mapped interpolation (MI)

algorithm can be used to interpolate the energy, the frequencies, the determinant of the

moment of the inertia tensor, and the curvature components to extend one or both ends of

the MEP for tunneling calculations. (See Sections 6.N.3 and 8.A for more details.)

When there is no saddle point a simple exponential extrapolation of the classical and

adiabatic energies and the other quantities used for tunneling calculations can be used at

one or both ends of the MEP. (See Sect. 10.A for more details.) The EXFIRST and

EXSECOND keywords in the PATH section control interpolation (extrapolation) options.

Interpolation (extrapolation) is especially useful in situations where a minimum is

reached in the classical potential before the adiabatic barrier is low enough for computing

converged tunneling probabilities. Notice that extending the grid is sometimes called

extrapolation, but it is also called interpolation because one used the reactant or product

information that technically it is indeed interpolation.

When the MEP calculation is completed, the reaction-path information can be saved by

writing it to unit fu1 for later restart runs. We note that there is an upper limit of NSDM

points at which the reaction path information can be saved in a given Polyrate executable

file. The parameter NSDM is defined in the file aamod.f90 (see Subsection 5.A.2).

In the electronic structure input file case, the geometries, energies, vibrational frequencies

or harmonic force constant matrices, and (optionally) higher-order force constants of the

reactant(s), product(s), saddle point, and generalized transition states are read in from unit

fu30, fu31, or fu40. (A more detailed statement of the available input options is given in

Section 9.) The number of points on the MEP available from electronic structure

calculations is usually small; thus when converging tunneling probabilities it is

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sometimes necessary to extend the reaction path beyond the last input data point on one

or both sides of the MEP. This is done by specifying larger values for the SLM and SLP

keywords in the PATH section. The special interpolation procedures are described in

Subsections 9.C and D.

The generalized free energy of activation is then computed at each of the points on the

save grid (at which the reaction path information was saved), and the CVT rates are

calculated for an input set of temperatures (done in RATE). We find the maximum

generalized free energy of activation by local interpolation using 5-point Lagrangian

interpolation. The result calculated with 3-point Lagrangian interpolation is printed as a

check.

Various tunneling corrections can also be included by a call to KAPVA. The final output of

forward and reverse reaction rate constants with and without the various tunneling

corrections, as well as output of activation energies, analyses of bottleneck properties,

equilibrium constants, and the ratio of the CVT to the conventional transition state theory

rate constants, are provided by FINOUT.

If the VTST-IOC option is selected (DL keyword set to ic or ICOPT keyword specified),

the program will then update (done in ZOCUPD) all the MEP information based on

corrections calculated from the higher-level values read from the unit fu50 input file and

calculate a new set of rate constants based on the corrected values by the same

procedures as described above.

If the VTST-ISPE option is selected (DL keyword set to ispe), the program will update

the energies along the MEP based on a spline fit to the differences of the lower-level

energies and the higher-level energies read from the unit fu51 input file. A new set of

rate constants is then calculated, based on the corrected energies, by the same procedures

described above.

If the IVTST-0 method is selected, after the MAIN program reads all the information

provided at reactants, products, and saddle point, subroutine GIVTST is called. Then the

process of generating the information required at points along the reaction path by

interpolation is started using specific routines for IVTST instead of the ones employed

for calculations based on analytic potentials or fu30, fu31, and fu40 input files. If the

IVTST-1 method is selected, the electronic structure information at the stationary points

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plus the data at an extra point located close to the transition state is read by the MAIN

program from file fu29 and then the subroutine GIVTST is called.

7.B. Determining the sign of s

If there is a saddle point, the reaction coordinate s is, by convention, positive on the

product side of the saddle point and negative on the reactant side. In the program,

however, the default is that s is defined as positive in the direction of the unbound normal

mode at the saddle point, and it is defined as negative in the opposite direction. When

one is using the hooks, the definition of the sign of s does not affect the calculated rate

constants when LCG3 or LCG4 calculations including tunneling into excited states are

not carried out, but it does affect the LCT probabilities when contributions from

tunneling into excited states are included, since the current coding of that case requires

consistency with the convention. When one is using fu30, fu31, or fu40, the choice of

SIGN also affects whether SCT calculations or LCT tunneling into the ground state are

correct, as explained in the next paragraph. Also, confusion might arise when one

specifies the range of the reaction path to be calculated or discusses the location of the

optimized variational transition state. We therefore advise users to override the default, if

necessary, to follow the established convention of s being positive on the product side.

The following procedure is recommended to ensure this. First, make a run without

computing the path (do not include the PATH section) and without computing the

properties of reactants and products (do not include REACT1, REACT2, PROD1, and/or

PROD2 sections), and look at the normal mode eigenvector corresponding to the normal

mode with imaginary frequency at the saddle point. If this vector points towards

products, set the SIGN variable keyword in the PATH section to product in full runs. If

not, set it to reactant (or omit it, since reactant is the default). There is another

keyword, IDIRECT, in the PATH section which determines the direction of the first step

from the saddle point in calculating the MEP. If SIGN is set correctly and if IDIRECT is set

to 1 (which is the default), the MEP toward the product side (which is determined by the

keyword SIGN discussed above) will be calculated first and the reactant-side MEP will be

calculated after the limit on the product-side MEP is reached. If SIGN is set correctly and

if IDIRECT is set to −1, the reactant-side MEP will be calculated first instead. The value

of IDIRECT should not affect the calculated results.

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In practice, the SIGN variable works differently with the hooks and with files 30, 31, and

40. When one is using the hooks, SIGN actually changes the sign of the value of s that is

assigned to given geometry on the reaction path. When one is using the electronic

structure input file options, one cannot change the sign of s. However, it is still necessary

that SIGN be set correctly. If SIGN is set wrong, then the reaction path curvature at the

saddle point will not be computed correctly. The correct setting for SIGN when one is

using fu30, fu31, or fu40 is determined by the following rule: when using fu30, fu31, or

fu40, if the positive direction of s in the output is not associated with the direction toward

products, then change the choice for the SIGN variable in the PATH section of the input

and repeat the run.

7.C. Restart options

There are two ways to restart calculations in POLYRATE.

The first restart option is controlled by the RESTART keyword in the GENERAL section.

This option is designed to allow calculations at additional temperatures without

recalculating the information stored on the save grid. This option uses fu1. If the VTST-

IOC option is used with RESTART, one can change the lower level but not the higher level,

i.e., the fu50 file cannot be changed for the RESTART run. Furthermore, if the original run

was not a dual-level run, the restarted run cannot be a dual-level run.

The second restart option allows one to restart calculations without repeating all of the

work for the stationary points (reactants, products, and/or saddle point). This restart

option is controlled by the STATUS keyword in the REACT1, REACT2, PROD1, PROD2, and

START section. Each of the input sections for the stationary points (REACT1, REACT2,

PROD1, PROD2, and START) allows one to input optimized geometries, energies, and

frequencies from previous jobs. The user also has the option of only calculating

reactants, or only calculating products, or only calculating a saddle point to obtain the

optimized geometries, energies, and frequencies for the given stationary point before

proceeding with the rest of the calculation. Thus it is possible to optimize the stationary

points in separate runs, and then read in the data for those stationary points in later runs to

continue. To do this, the user can run Polyrate with only the *GENERAL, *ENERGETICS,

*SECOND, *OPTIMIZATION, *REACT1, and *REACT2 sections in the fu5 file. If the

calculation is a supermolecule calculation then both reactant 1 and reactant 2 must be

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specified in the *REACT1 and *REACT2 sections. However, if the calculation is not a

supermolecule calculation then it is possible to calculate reactant 1 and reactant 2

separately using only the *REACT1 section and leaving out the *REACT2 section. Note

that when calculating only reactant 2, the information for reactant 2 is placed in the

*REACT1 section and the *REACT2 section is left out. The same scenario holds for

products, i.e., one can include *REACT1 or *REACT1 and *REACT2 but leave out *START.

If the user wishes to optimize the saddle point without optimizing the reactants and

products then the saddle point information is placed in the *START section and Polyrate is

run with only the *GENERAL, *ENERGETICS, *SECOND, *OPTIMIZATION, and *START

sections in the fu5 file. An fu61 file, which contains the optimized properties, is created

after every Polyrate run. The information on this file can be used to build a complete fu5

file or update an existing fu5 file with optimized information. Thus, effectively, one can

optimize each stationary point separately or in any combination of stationary points, add

the newly optimized information to an existing or a new fu5 file, and restart the

calculation to optimize the remaining stationary points or complete the full calculation.

See Section 12.A.6.

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8. CALCULATIONS USING THE HOOKS

8.A. Methods for interpolating beyond SLM and SLP with the hooks

This section describes the procedures used when interpolating between the SLM end point

on the save grid and the reactants and between the SLP end point on the save grid and the

products, respectively. There are two procedures that are used. Note that SLM and SLP

keywords are only for MEP, and invalid for variable reaction coordinate.

The first procedure is used when the reaction being studied has a saddle point. (In this

case the SADDLE keyword in the PATH section is specified or taken as the default.)

Reactions with saddle points either do not involve interpolation, or they use the mapped

interpolation (MI) algorithm to extend the reaction path beyond SLM and SLP. The

options for this interpolation are controlled by the EXFIRST and EXSECOND keywords in

the PATH section. The MI algorithm is described in Sections 6.N.2, 6.N.3, and 10.J and in

Ref. 48 of Sect. 21.

The second procedure is used when the reaction being studied does not have a saddle

point. For this type of reaction the NOSADDLE keyword must be specified in the path

section. Reactions without saddle points always use a two-point extrapolation to extend

the reaction path beyond SLM and SLP. The options for this extrapolation are controlled

by the EXFIRST and EXSECOND keywords in the path section. The two-point extrapolation

is described in Section 10.A.

8.B. Zero of energy

In Polyrate the variable EZERO always denotes the energy that corresponds to reactants in

the potential energy subroutine, and it is used to convert the potential energy to the zero

of energy that is used in the rest of POLYRATE. EZERO refers to the energy of a single

reactant (for a unimolecular reaction) or the sum of energies of infinitely separated

reactants (for a bimolecular reaction). In the language of potential energy surfaces,

EZERO denotes the potential energy of the reactant or reactants at their classical

equilibrium geometries. In the language of electronic structure calculations, EZERO

denotes the sum of the electronic energy and the nuclear repulsion (for ab initio

calculations). It is necessary to understand this variable in order to understand the input

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options available with the EZERO keyword in the GENERAL section; the rest of this section

provides the necessary explanation.

In Polyrate the user must ensure that EZERO is set equal to a value consistent with the

potential energy subprogram (when an analytic potential energy subprogram is used) or

with the electronic structure data (when the electronic structure input file option is used).

This can be accomplished in one of two ways: (i) by setting the EZERO keyword to

calculate and letting the program calculate the zero of energy, or (iii) by setting the

EZERO keyword to read and directly inputting a nonzero value for EZERO which is

consistent with the potential energy subprogram.

Setting the EZERO keyword to be equal to calculate causes the program to calculate

the zero of energy after the reactants have been optimized to their equilibrium geometries

at "infinite" separation. Because the zero of energy is not computed until the

optimization procedure, all energies for the reactant species which are printed to the long

output file on unit fu6 before the zero of energy is computed will have an incorrect zero

of energy. For a unimolecular system the zero of energy is set equal to the potential

energy of the system at its optimized reactant equilibrium geometry. For a bimolecular

system the zero of energy is set equal to the sum of the potential energies of the two

reactants after both reactants have been optimized to their equilibrium geometries. This

can be done with the SUPERMOL option by placing the two reactants at a large separation

distance given implicitly by the two geometries specified by the GEOM keyword in the

REACT1 and REACT2 sections of the unit fu5 input data file. (Note that, when the

SUPERMOL option is used, this sum is given by the energy at the end of the second

reactant's optimization).

8.C. User-Supplied analytic potential energy surface

8.C.1. Interface

The protocol of the subprograms for evaluating the potential energy from an analytic

function is as follows. The user must supply two subroutines, SETUP and SURF, which

accept and return all information from and to Polyrate in atomic units. The subroutine

SETUP has one integer type variable, n3tm, in its parameter list:

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subroutine setup (N3TM)

In the argument list of the call statement to SETUP the Polyrate code passes the variable

N3TM where:

N3TM = 3 NATOMS

(This variable is used to dimension the arrays for the Cartesian

coordinates and the derivatives of the energy with respect to the

Cartesian coordinates for a given system.)

NATOMS = maximum number of atoms in the Polyrate code

(It is the actual number of atoms in the system set in the input

file.)

SETUP may optionally open data file(s) which contain the potential parameters, read these

parameters, set up any necessary data, and close any file(s) which were opened. SETUP is

called once and only once in each complete run of the program.

Note that SURF and SETUP are called by the hooks. In particular, SETUP may be called by

PREP and/or PREPJ, and SURF may be called by EHOOK, GHOOK, HHOOK, and OHOOK.

No other routines call SURF and SETUP.

Users should dimension arrays in SETUP carefully since inconsistency of array

dimensioning is the major potential source of error when passing information between

subprograms. Also, users should resolve any conflict in the assignment of the input and

output I/O units between Polyrate and SETUP. For the I/O unit numbers used by

POLYRATE, see Section 19. As noted there, unit 4 is reserved for use by the potential

routines, i.e., by SETUP. If SETUP requires more than one file, unit 7 is recommended for

the second file. Alternatively the FU# parameters in the aamod.f90 file can be modified

to avoid conflicts between the FORTRAN units used in Polyrate and those used by SETUP

and SURF. In addition, users should not name subroutines with the same name as an

existing Polyrate subroutine. A list of subroutine names and a short description of the

subroutines used by Polyrate are given in subsection 17.A.1.

The subroutine SURF evaluates the potential and its first derivatives as functions of the

Cartesian coordinates, and it has 4 elements in its parameter list. These are V, X, DX, and

N3TM, as follows:

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subroutine surf (V, X, DX, N3TM)

where:

V = potential energy in hartrees

X = array of dimension N3TM which contains the Cartesian

coordinates in bohrs of all the atoms in the system

DX = array of dimension N3TM which contains the first derivatives (in

hartrees per bohr) of the energy with respect to each of the

Cartesian coordinates. DX should be determined analytically if

possible as all higher-order derivatives needed by Polyrate are

calculated numerically from these first derivatives.

N3TM = as defined above

The arrays X and DX must be of dimension N3TM within the subroutine SURF.

The order of the coordinates is (x, y, z) for atom 1, (x, y, z) for atom 2, ..., (x, y, z) for

atom N, where the order of the atoms is determined by the order used in the ATOMS list

keyword in the GENERAL section. (see Subsection 12.A.2).

Note that whenever the potential is read from FORTRAN unit fu30 file, SURF and SETUP

are not needed and may be replaced by their dummy versions, for example, those

included in the dumpot.f file.

During the calculation of the MEP, the quantities V, X, and DX are optionally written

(using the PRSAVERP keyword in the PATH section) by Polyrate to the file linked

to the FORTRAN unit fu6 for each point at which reaction path information is

saved (each save grid point). Since the user is often interested in the values of

additional quantities calculated by subroutine SURF (such as interatomic distances,

curvilinear internal coordinates, or various contributions to the potential energy)

at these save points, we also provide the array POTINF(NPOTPT) in rate_const

module in the Polyrate program as a means of passing such information from

subroutine SURF to the main program, in which the array POTINF is optionally

written to the file linked to the FORTRAN unit fu6. (This is controlled by the use

of the POTINF keyword in the PATH section). The maximum number of pieces of

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data from the potential which may be printed at each save grid point is 99. Unlike

the parameter lists described above, the use of the common block SURFCM in the

user-supplied SURF subroutine is user-driven. The information stored in the array

POTINF is printed exactly as stored. Note that values assigned to the array POTINF

have no effect on any values calculated by POLYRATE.

8.C.2. Utility routines

The Polyrate program assumes that the user-supplied potential energy function

subprogram SURF accepts the values of the atomic Cartesian coordinates and returns the

potential energy and the derivatives of the potential energy with respect to the atomic

Cartesians. However, not all potential energy functions are written in terms of atomic

Cartesians; some potential energy functions are written in terms of bond lengths. With

this in mind, four utility subprograms are provided with POLYRATE. Two of the utility

subprograms are for three-body systems and the other two are for four-body systems.

Two types of utility subprograms are provided. One type converts atomic Cartesians to

bond lengths, and the other uses the chain rule to convert the derivatives of the energy

with respect to the bond lengths to derivatives with respect to the atomic Cartesians.

The subprograms COORD#, where # = 3 for a three-body system and # = 4 for a four-body

system, convert the atomic Cartesians to bond lengths. In the case of COORD3, nine

Cartesians are converted to three bond lengths. The order of the Cartesians and the bond

lengths are as follows:

X(1) — X(3): X, Y, Z for atom A

X(4) — X(6): X, Y, Z for atom B

X(7) — X(9): X, Y, Z for atom C

R(1): R(A−B)

R(2): R(B−C)

R(3): R(C−A)

The Cartesians are passed to COORD3 through the parameter list (X, N3TM) (X and N3TM

are defined in Subsection 8.C.1) and the bond lengths are passed to the potential

subprogram through the module POTCM3:

module potcm3

integer :: nsurf, nder, ndum(8)

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real(8) :: r(3),energy, dedr(3)

end module potcm3

COORD3 assumes that all the coordinates (Cartesians and bond lengths) are in atomic

units. The subprogram also assumes that the potential is written such that the bond

specifications are as defined above. For example, if the potential for ClHBr is written

such that

R(1): R(Cl−H)

R(2): R(H−Br)

R(3): R(Br−Cl)

the user must define Cl as the first atom (atom A), H as the second atom (atom B), and Br

as the third atom (atom C) in the input data in unit fu5.

The subprogram COORD4 does the same calculation as COORD3 but for a four-body

system. In COORD4 the coordinates are defined as follows:

X(1) — X(3): X, Y, Z for atom A

X(4) — X(6): X, Y, Z for atom B

X(7) — X(9): X, Y, Z for atom C

X(10) — X(12): X, Y, Z for atom D

R(1): R(A−B)

R(2): R(A−C)

R(3): R(A−D)

R(4): R(B−C)

R(5): R(B−D)

R(6): R(C−D)

The subprograms CHAIN#, where # = 3 for a three-body system and # = 4 for a four-body

system, convert the derivatives of the energy with respect to the bond lengths to

derivatives with respect to the atomic Cartesians. In the case of CHAIN3, three derivatives

with respect to the bond lengths are converted to nine derivatives with respect to the

atomic Cartesians. The order of the derivatives is as follows:

DEDR(1): DEDR for the bond length A−B

DEDR(2): DEDR for the bond length B−C

DEDR(3): DEDR for the bond length C−A

DX(1): DEDX for atom A

DX(2): DEDY for atom A

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DX(3): DEDZ for atom A

DX(4): DEDX for atom B

DX(5): DEDY for atom B

DX(6): DEDZ for atom B

DX(7): DEDX for atom C

DX(8): DEDY for atom C

DX(9): DEDZ for atom C

The derivatives with respect to the bond lengths are passed through the common block

POTCM as defined above, and the Cartesian information is passed through the parameter

list (X, DX, N3TM). This subprogram assumes the same definitions as COORD3.

The subprogram CHAIN4 performs the same calculation as CHAIN3, but for a four-body

system with the following coordinate definitions:

DEDR(1): DEDR for the bond length A−B

DEDR(2): DEDR for the bond length A−C

DEDR(3): DEDR for the bond length A−D

DEDR(4): DEDR for the bond length B−C

DEDR(5): DEDR for the bond length B−D

DEDR(6): DEDR for the bond length C−D

DX(1): DEDX for atom A

DX(2): DEDY for atom A

DX(3): DEDZ for atom A

DX(4): DEDX for atom B

DX(5): DEDY for atom B

DX(6): DEDZ for atom B

DX(7): DEDX for atom C

DX(8): DEDY for atom C

DX(9): DEDZ for atom C

DX(10): DEDX for atom D

DX(11): DEDY for atom D

DX(12): DEDZ for atom D

These subprograms can be used with any three- or four-body potential, which is written

in terms of bond lengths. For example, for a three-body potential made up of two

subprograms, PREPOT and POT, where PREPOT does the initializations for the potential, i.e.

performs the role of SETUP, and POT does the actual potential and derivative evaluations

given the geometry in terms of bond lengths, the user could provide SETUP and SURF

routines to link Polyrate with PREPOT and POT.

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The subprogram SETUP would simply call PREPOT. For example:

subroutine setup (n3tm)

implicit double precision (a-h, o-z)

call prepot

return

end

The SURF subprogram would first call COORD3, then call POT, and then call CHAIN3 before

returning to the Polyrate program. For example:

subroutine surf (v, x, dx, n3tm)

implicit double precision (a-h, o-z)

use potcm3

dimension x(n3tm), dx(n3tm)

call coord3(x, n3tm)

call pot

v = energy

call chain3 (x, dx, n3tm)

return

end

8.D. Calculations using an electronic structure program through hooks

A very useful feature of the Polyrate program is its ability to link an electronic structure

program to obtain reaction path information directly. All energetic information needed

by Polyrate for single-level runs or for the lower level of a dual-level run is obtained in

one of two ways. The first way is via a set of general hook routines. The second way is

from an electronic structure file (fu29, fu30, fu31, or fu40). This section of the manual

describes the hook routines.

The hook routines are actually quite general. They can be used to call an analytical

potential surface, and this special case is described in section 8.C. Alternatively they

could be used for direct links to electronic structure programs (as in MORATE,

GAUSSRATE, GAMESSPLUSRATE, JAGUARATE, or NWCHEMRATE) or in any way that the user

finds useful. In the case of the connection to an electronic structure program, the user is

responsible for obtaining or writing the necessary routines that interface the hook routines

and the electronic structure program. In some cases, e.g., MORATE, GAUSSRATE,

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GAMESSPLUSRATE, JAGUARATE, and NWCHEMRATE such interface routines have been

prepared by Polyrate developers, but users are invited to prepare their own interface

routines as well.

We note that historically Polyrate called SURF and SETUP directly. Beginning with

version 7.0, the hooks were inserted as an interface between the Polyrate program and the

source of potential information. The goal is for Polyrate to be completely blind as to

what happens on the other side of this interface. We refer to this as complete modularity

between the dynamics and the potential, and we believe that this modularity has been

fully accomplished since version 7.3.

The hook routines are PREP, PREPJ, EHOOK, GHOOK, HHOOK, and OHOOK. The source

code for these routines is located in the src/ subdirectory in hooks.f. This subdirectory

also contains six utility subprograms (YTRANS, YSECEN, YSECEP, YDERV2, YDER24, and

YNEWT). The role of each of the hooks is described below. Before proceeding with these

individual descriptions, we first make a few general comments. The basic concept of the

hooks is as follows: Whenever Polyrate needs an energy, it calls EHOOK. Whenever

Polyrate needs a gradient (or an energy and a gradient at the same geometry) it calls

GHOOK. Whenever Polyrate needs a Hessian (or a Hessian plus an energy and/or

gradient, all at the same geometry), it calls HHOOK. Polyrate has its own geometry

optimization routines, and it may employ them using energy, gradient, and/or Hessian

information from calls to EHOOK, GHOOK, and HHOOK. However, in many cases it is

more efficient to call external optimization routines. These can be accessed by calls to

OHOOK. Finally, we note that PREP and PREPJ are available for initialization tasks, i.e.,

for passing geometry-independent information to the other side of the interface.

The versions of the hooks distributed with Polyrate itself only call SURF and SETUP,

except for HHOOK, which calls GHOOK. This does not convey the full usefulness of the

hooks. The hooks are better appreciated by studying one of the direct dynamics codes

built on Polyrate, e.g., MORATE, GAUSSRATE, GAMESSPLUSRATE, JAGUARATE, and

NWCHEMRATE. But the Polyrate versions of the hooks provide clear examples of their

use that can be understood by all users, independent of whichever electronic structure

codes they are familiar with.

Since version 7.3, HHOOK computes Hessians by taking numerical derivatives of

gradients obtained by calls to GHOOK. The code is identical to the code for this purpose

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on the Polyrate side of the interface. As mentioned in the previous paragraph, this does

not convey the full power of this hook. This hook is designed to allow the user to take

advantage of analytic Hessians if they are available. If analytical Hessians are available,

the user should modify HHOOK to use them. A similar generic version of OHOOK is also

provided.

PREP:

PREP is the driver for all preparation routines needed to set up the hooks. This routine is

called once after input file fu5 has been read in and before the table of input is written to

the output file. This call occurs before any calculations are done. This routine may be

used to call electronic structure preparation routines. File fu70 is reserved for use by

PREP.

To interface with a new electronic structure program one just needs to add a new block to

the ‘if block’ contained in this subroutine with a call to the appropriate routine. Note that

this is an optional hook. Not all electronic structure programs need initialization. When

PREP is not needed, one should use a dummy routine with a simple return command

inside.

PREPJ:

PREPJ is the species-dependent driver for all preparation routines needed to set up the

hooks. Any initializations that are dependent on whether the reactants, products, saddle

point, or generalized transition state is computed are done here. PREPJ is called up to six

times, namely it is called once each at the starts of the sections for REACT1, REACT2,

PROD1, PROD2, START, and PATH. In other words, PREPJ is called before each respective

reactant, product, or saddle point is studied and again before the reaction path is

computed. A variable, JTYPE, specifies which particular species is being computed; see

Section 19 on file usage.

To interface with a new electronic structure program one just needs to add a new block to

the 'if block' contained in this subroutine with a call to the appropriate routine. Note that

this is an optional hook. Not all electronic structure programs need any species

dependent initializations. When the PREPJ is not needed, user should prepare a dummy

routine with a simple return command inside.

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EHOOK, GHOOK, HHOOK, and OHOOK always communicate with the Polyrate side of the

interface using mass-scaled Cartesians in bohrs and energies in hartrees. In the versions

of the hooks distributed with POLYRATE, either mass-scaled Cartesians or unscaled

Cartesians may be used for communicating with SURF. In the versions of SURF that are

distributed with POLYRATE, the energy is computed using the Cartesian coordinates, so the

hooks first convert to unscaled Cartesians before calling SURF. Similar transformations

are required for gradients and Hessians; for example, SURF returns gradients in unscaled

coordinates, but GHOOK converts them to mass-scaled coordinates.

EHOOK:

EHOOK is the energy interface subprogram of Polyrate.

To interface with a new electronic structure program, one needs to add a new block to the

'if block' with a call to an interface routine that accepts Cartesian coordinates (unscaled)

and returns the energy. If the read option is chosen for the EZERO keyword, then the

zero of energy should be consistent with the EZERO value specified in the input file.

Remember that the user must also specify the new interface potential by adding another

option to the POTENTIAL keyword and implementing the new possible value of the

associated IPOT variable in the FORTRAN code.

GHOOK:

GHOOK is the gradient (first derivative) interface subprogram of Polyrate.

To interface with a new electronic structure program, one needs to add a new block to the

'if block' with a call to an interface routine that accepts Cartesian coordinates (unscaled)

and returns the energy and first derivatives. The developer of a new interface must also

specify the new interface potential by adding another option to the POTENTIAL keyword

and implementing the new possible value of the associated IPOT variable.

HHOOK:

HHOOK is the Hessian (second derivative) interface subprogram of Polyrate.

For the second derivatives, the potential is specified by the HESSCAL keyword of the

SECOND section of the fu5 input file and is coded in FORTRAN using the IPOT variable.

If the keyword option ghook is used in the HESSCAL keyword, numerical difference

methods from Polyrate are applied; if the hhook option is used, then the second

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derivatives are taken from HHOOK. The latter option is designed to allow HHOOK to

obtain analytic second derivatives from electronic structure routines. In the current

version of POLYRATE, the ghook and hhook options are essentially the same. If the

hhook option is used, the second derivatives are computed with the hooks routines

YSECEN and YSECEP, whereas if the ghook option is used, the second derivatives are

computed with Polyrate subroutines SECCEN and SECCEP. However, the numerical

methods used in YSECEN and YSECEP are the same as those in SECCEN and SECCEP.

HHOOK must convert the Hessian to mass-scaled coordinates before returning to the

Polyrate side of the interface.

To interface with a new electronic structure program, one needs to remove the subroutine

calls in the ISPOT equals to 1 block and add a new block with a call to an interface routine

that accepts Cartesian coordinates (unscaled) and returns the energy, first derivatives, and

Hessian matrix. Note one must ensure that the gradient and Hessian conform to the same

orientation. See subsection 12.A.4 for the description of the keyword options used to

calculate second derivatives.

OHOOK:

OHOOK is the geometry optimization interface subprogram of Polyrate. This routine

accepts an initial guess to the mass-scaled Cartesian coordinates of the full system and

returns the optimized geometry in mass-scaled Cartesian coordinates and the energy. A

variable, IOP, is used to specify which chemical species is being optimized: for IOP = 1,

or 2; the chemical species is reactant 1 or 2, for IOP = 3, or 4; the chemical species is

product 1 or 2; for IOP = 5, the chemical species is the saddle point.

The geometry optimization is specified by the OPTMIN and OPTTS keywords and is coded

in FORTRAN using the IGPOT variable. If the keyword option bfgs or nr is used for

either of these keywords, IGPOT is 0, and the optimization is performed by NEWT, which is

a Polyrate subroutine. The OHOOK option (IGPOT = 1) is designed to allow the OHOOK

routine to call an electronic structure package directly. In the generic version of the

OHOOK routine, the option calls YNEWT, which is supplied as part of the generic hooks.

(Notice that YNEWT is a slightly simplified version of the Polyrate routine NEWT.) To

interface with a new electronic structure program, one must replace the call to YNEWT

when IGPOT equals to 1 with a call to an interface routine that accepts Cartesian

coordinates (unscaled) and returns the optimized geometry and energy. Notice that, in

the current version of POLYRATE, the method used to optimize the minima and saddle

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point should be the same (i.e. either both from Polyrate or both from electronic structure

package). For the description of the keyword options used in geometry optimization, see

subsection 12.A.5.

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9. CALCULATIONS BASED ON AN ELECTRONIC STRUCTURE INPUT FILE

One major option of the Polyrate program is the ability to use MEP information obtained

from electronic structure calculations in the form of an input file instead of using an

analytic potential energy surface. This input file will contain MEP information for a

finite range of the reaction path, namely s in the interval [SLM, SLP]. It is the user's

responsibility to ensure that these input geometries do indeed lie on the MEP or a good

approximation to it.

When one of the electronic structure files (fu30, fu31, or fu40) is used the Polyrate

program is never supposed to make calls to the potential energy surface subprograms

SETUP and SURF. However, to satisfy all external references when linking the program

the subprograms SETUP and SURF must be provided. A potential energy surface file,

dumpot.f, distributed with the Polyrate program has been designed specifically for use

with this option of the code. This potential energy surface file contains dummy SETUP

and SURF routines which print a warning message and stop if subprogram SURF is called.

When the reaction-path information is calculated from electronic structure calculations

and is used as input for dynamical calculations, the necessary information (listed later in

this paragraph) is read from a separate data file which is linked to the FORTRAN unit

fu30, fu31, or fu40 and is keyed to the normal input in the file which is linked to the

FORTRAN unit fu5. Throughout this manual, unit fu30, unit fu31, and unit fu40 are

called the electronic structure input files. The input data in unit fu5 remains the same as

when the calculation is done with an analytic potential energy surface except that the

POTENTIAL variable keyword in the GENERAL section is set to unit30, unit31, or

unit40. A line-by-line description of the MEP input for unit fu30 is provided in

Section 12.C, a description of the input when using unit fu31 is given in Section 12.D.,

and a description of the input when using unit fu40 is provided in Section 12.E. Using

the information from unit fu30, unit fu31, and unit fu40, the quantities V(s), |I(s)|, w(s) ,

k3(s), k4(s), and BmF(s) are interpolated to locations on the save grid and are stored in

save grid arrays to be used for Lagrangian interpolation as needed for finding variational

transition states and as needed for tunneling calculations. The type of information used

to obtain the tables of the MEP quantities is as follows:

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Potential

 

VMEP(s) is always read directly.

Determinant of the moment of inertia tensor

|I(s)| is always computed from the geometry of the complex. For reactants and

products at infinite separation |I(s)| is infinite, so for large |s| the program

interpolates the inverse of |I(s)| instead of |I(s)| itself. To obtain |I(s)|for finite s it

is necessary to read the 3N Cartesian coordinates R(s) or the mass-scaled ones

x(s).

Gradients

The gradient must be read in. The gradient is denoted DX. The code

has options to read either the gradient itself or the negative of the gradient, which is

the force. In addition, the gradient or force may be in either unscaled or mass-

scaled coordinates.

Frequencies

w(s) can be read directly or computed from the force constant matrix F(s). If

F(s) is read, both w(s) and the coefficient matrix L which diagonalizes F (or the

projected F) are obtained. A total of 3N-7 (for a nonlinear generalized transition

state), 3N-6 (for a linear generalized transition state), or 3N-1 (for solid-state or

gas-solid interface generalized transition state) frequencies or a 3N 3N force

constant matrix is read.

Anharmonicities

Either the cubic and quartic force constants k3(s) and k4(s) are read directly, or

they are omitted. If read, a total of 3N-7 (nonlinear), 3N-6 (linear), or 3N-1

(solid-state or interface) of each will be read. Even if k3(s) and k4(s) are not read,

anharmonicities can still be included by using the Morse I approximation.

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Reaction-path curvature

The reaction-path curvature components BmF(s) can either be read in or they can

be computed from the gradients. These curvature components are needed for SCT

calculations but are not used for CVT or ZCT calculations.

The user should always supply the following information for all points on the Hessian

grid: s, VMEP , the geometry, the gradient, and either the frequencies or the Hessian.

Depending on the options chosen, one or more of the following should also be supplied

for all points on the Hessian grid: the frequencies, the Hessian (i.e., the matrix of second

derivatives of the potential), the cubic force constants, the quartic force constants, and the

curvature components. Alternatively, the curvature components can be calculated by the

program. For this purpose, when using files fu30 or fu40, the program can use only the

gradients at the save points or it can use the gradient at up to two additional s values on

either side of each Hessian point. However only the latter option is available when using

file fu31.

The user must also supply information about the reactants and the products, if it is

needed.

9.A. Relation of Polyrate input to electronic structure package output

GAUSSIAN94 prints the forces on the standard output file, and it prints the gradients on the

formatted check point file; however, on the latter the gradients are incorrectly labeled as

forces. We prefer to take the gradients from the formatted checkpoint file because

GAUSSIAN’s output format on the formatted checkpoint file is more similar to POLYRATE’s

input format (for fu30, fu31, and fu40), so the user can directly cut and paste.

A different issue arises when one uses the GAMESS electronic structure package. GAMESS

writes the gradient in both un-normalized and normalized form. Polyrate requires the un-

normalized gradient if one uses curvilinear coordinates, so the user should be sure to take

the gradient from the correct place in the GAMESS output.

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9.B. Orientation of the molecule at generalized transition states

When an electronic structure calculation program is used to determine the optimized

structures for the generalized transition states, the electronic structure code sometimes

translates and/or rotates the molecule to a “standard”, a “Z-matrix”, or other orientation.

However, Polyrate requires precisely the orientation obtained by following the minimum

energy path in mass-scaled Cartesians. For example, if the ESD method is used, the

points along the path should be related by equations (26) and (27) of the GTST book

chapter [Ref. 5 of Sect. 21]. Using an incorrect orientation can introduce errors in the

gradients and curvatures and can result in errors in the tunneling calculations. The user

of Polyrate is urged to be very cautious in understanding these issues if he or she uses an

electronic structure package that re-orients the molecule. Special keywords are

sometimes required to prevent re-orientation.

For example, for single-point calculations that ask for a gradient or a Hessian or both,

when the GAUSSIAN input has the geometry in Cartesian coordinates and the NOSYMM

keyword is specified, then GAUSSIAN will not re-orient the molecule, and the gradients

and Hessians that it prints out in the formatted checkpoint file (Test.FChk file) are

consistent with the orientation of the input geometry. Notice that it is impossible to avoid

re-orientation of geometry if the Z-matrix is given in internal coordinates, since

GAUSSIAN automatically generates a set of Cartesian “Z-matrix” coordinates in which the

first atom is placed at the origin, the second one on the Z axis, and the third one in the X-

Z plane. This can be avoided using Cartesian coordinates for defining the input

geometry. A second aspect of GAUSSIAN the user should be aware of is that even when

using Cartesian coordinates for the input geometry in single-point calculations, if the

NOSYMM keyword is not specified, both the gradient and the force constants matrix

written to the formatted checkpoint file will correspond to a geometry translated and re-

oriented according to what GAUSSIAN calls the “standard orientation”. However, notice

that the forces and the force constants matrix printed out in the GAUSSIAN long output file

are still consistent with the initial input geometry orientation; thus they can be used for

dynamics without introducing errors in the calculation.

Re-orientation issues are more complicated when one considers reaction paths. It appears

to be impossible to generate a reaction path with GAUSSIAN without having the

geometries re-oriented if the transition state geometry required to perform a reaction path

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calculation is input in internal coordinates. However, if the geometry of the transition

state is given in Cartesian coordinates, and if the computed force constants are also read

in Cartesian coordinates from a checkpoint file corresponding to a frequency calculation

performed including NOSYMM in the keyword list, the reaction path will have the correct

orientation to be used in a direct dynamics calculation. Whether the NOSYMM keyword is

or is not used in the actual reaction path calculation does not affect the origin or the

orientation of the respective points.

An alternative method that we have used in the past to generate the reaction paths is to

employ the electronic structure package GAMESS. However, although GAMESS can be

used to generate a non-re-oriented reaction path, we could not find a convenient way to

prevent GAMESS from re-orienting when it calculates the gradients and Hessians. (We did

find a way to avoid re-orientation, but it is inconvenient because it re-orders the atoms.)

One solution is to use GAMESS to generate un-re-oriented geometries along the reaction

path, and then use GAUSSIAN (with Cartesian coordinates input and NOSYMM) to generate

gradients and Hessians in a formatted checkpoint file. Our test of GAMESS were done

with the 9-11-96 version.

9.C. Methods for interpolation of electronic structure data with files fu30 and fu40

This section describes the procedures used with file fu30 when LOPT(2) is positive or with

file fu40 when MAXLPTS is positive.

For values of s between those on the input grid, the MEP quantities are obtained by n-

point Lagrangian interpolation. The maximum number of points used in the interpolation

is input to the program; the actual number of interpolation points is the minimum of this

input value [LOPT(2) in unit fu30] and the total number of points in the grid. Thus, if only

3 points are used in the grid, only up to second order Lagrangian interpolation can be

used.

For unimolecular reactions, association reactions, or reactions with wells, the reactant,

product, or well geometry (or both) will occur at finite values of s. In these cases

Lagrangian interpolation is also used for values of s approaching the reactant, product, or

well s value.

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In runs using analytic potential energy functions, there are two grids: (i) the fine grid,

also called gradient grid, with step size s = SSTEP and (ii) the save grid, where

frequencies and the Hessian are calculated and stored, with step size s = INH * SSTEP.

See also sections 7, 10.D, and 12.A.7.

In runs using file fu30 or file fu40, there are three grids which are similar to the two grids

described above; however their use is somewhat different; also their step sizes are

determined differently. First is the gradient grid. This consists of all the s values at

which gradient information is read in records 35, 38, or 41 of unit fu30 or the equivalent

records of unit fu40. This grid is not required to be evenly spaced, so s does not exist,

and the SSTEP value read from fu5 is ignored. Second is the basic input grid, which is

called the sparse grid in Ref. 14 of Sect. 21. When using file fu30, this is the same as the

gradient grid if LOPT(6) 2; it is a subset of the gradient grid if LOPT(6) is 3 or 4. The

basic input grid is the grid of points for which one reads energies in record 31 of unit

fu30 and either frequencies (record 46) or Hessians (record 44). Third is the save grid.

Input electronic structure information and calculated reaction path curvatures are

interpolated from the basic input grid plus saddle point information to the save grid by n-

point Lagrangian interpolation. The step size for the save grid is s = INH * SSTEP. This

interpolation can also be done by the IVTST-M method (For unit fu30, LOPT(2) = –1; for

unit fu40, the MAXLPTS keyword in *GEN40 is set to –1) instead of by n-point Lagrangian

interpolation. When using the IVTST-M method with files fu30 and fu40, the

interpolation can only be calculated with the default IVTST-M options.

A comment on the calculation of BmF(s) may be helpful here. When an analytic potential

is used, and the default value (dgrad) is accepted for the CURV keyword, BmF(s) is

calculated by a quadratic fit of points on the gradient grid; this fit is carried out in

subroutine BCALC. In this fit, one uses points with s 0 to calculate BmF(s) for s –s,

and one uses points with s 0 to calculate BmF(s) for s +s . Then one interpolates

between –s and +s to get BmF(s = 0). Notice that none of the quadratic fits involves

data with both s > 0 and s < 0. Thus in eq. (98) [see Section 24.A, item 15],

 

d sign(s)[ ]vig (s){ } /ds becomes

 

sign(s)[ ]dvig (s) /ds. In contrast, when an electronic

structure input file is used, files fu30, fu31, or fu40, one calculates BmF(s) by a quadratic

fit to points on the whole gradient grid in subroutine RPHB. Since it is now possible for a

given 3-point quadratic fit to involve both negative and positive s, the sign(s) function

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must be implemented before the fit is carried out because

 

sign(s)[ ]vig (s) is a continuous

function, but

 

vig (s) is not.

9.D. Methods for interpolation of electronic structure data with file fu31

This section concerns the procedures used with file fu31. The fu31 file is currently

incompatible with the IVTST0FREQ option. In version 2010, the ISPE and

FREQSCALE options are compatible. The default versions of these procedures may also

be used with file fu30 by setting LOPT(2) = –1 or with file fu40 by setting MAXLPTS = –1.

In runs using file fu31 there are also three grids, similar to those described above for files

fu30 and fu40, which store input and interpolated information. The gradient and the

basic input grids for file fu31 are the same as described above for files fu30 and fu40.

However, when using file fu31, the input grid information is always interpolated onto the

save grid using IVTST-M instead of by n-point Lagrangian interpolation. After data is

interpolated to the save grid, the rest of the calculation is the same as when using file

fu30 or fu40 or when using the hooks.

IVTST-M is described in Sections 6.N.2 and 10.J and in detail in Ref. 48 of Sect. 21.

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10. SELECTED DETAILS OF THE CALCULATIONS

Most of the methods used by the program are described in detail, including equations, in

the GTST book chapter (Ref. 5 in Sect. 21). All methods not discussed in the GTST book

chapter are described in the present section of the manual. See also Refs. 14, 29, 30, and

47 in Sect. 21.

Subsections 10.A-10.L describe in detail various options that may be used with either of

the two kinds of calculations—those based on an analytic potential energy surface or

those based on an electronic structure input file.

10.A. Extrapolation of the reaction-path data beyond the range of the original grid

In some cases the variational transition state lies in the interval [SLM, SLP], which is the

range of the save grid, but the tunneling calculation requires information over a wider

range of s to converge.

For reactions with a saddle point this is handled almost automatically by the mapped

interpolation (MI) algorithm, which allows one to extend the range of the reaction path

used without calculating more energies, gradients, or Hessians. For reactions with a

saddle point the MI algorithm is available to interpolate the energy, the determinant of

the moment of inertia, the frequencies, and the curvature components between SLM and

the reactants or SLP and the products. This may be thought of as an interpolation between

SLM and reactants and an interpolation between SLP and products, or it may be thought of

as an extrapolation beyond SLM toward reactants and beyond SLP toward products. (That

is why we sometimes call it interpolation and sometimes call it extrapolation.) The end

result is that all information is interpolated over the entire range from reactants to

transition state to products. The keywords EXFIRST and EXSECOND in the PATH section

control the options for the interpolation. If the EXFIRST and EXSECOND keywords are not

specified then no interpolation is performed. The MI algorithm is explained in Sections

6.N.2, 6.N.3, 10.J, and 12.A.7 and in Ref. 48 of Sect. 21.

For reactions without a saddle point and using RP-VTST Polyrate includes a simple two-

point extrapolation to extrapolate the vibrationally adiabatic ground-state potential and

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effective reduced mass,

 

meff , from the MEP end points to the reactants and/or products.

The asymptotic extrapolation procedures that may be used for reactions without a saddle

point are described in this subsection.

When using units fu30 and fu40 the two-point extrapolation is used by default to

extrapolate between the last save grid point and SLM or SLP. However, the IVTST-M

algorithm can be specified to interpolate between the last save grid point and SLM or SLP

by setting LOPT(2) = –1 for unit fu30 and by setting MAXLPTS = –1 for unit fu40. File

fu31 always uses the IVTST-M algorithm to interpolate from the last save grid point to

SLM or SLP. See Sections 6.N.2 and 10.J and Ref. 48 of Sect. 21 for more details about

the IVTST-M algorithm. In all cases, when using the electronic structure file input

options (units fu30, fu31, or fu40), the extrapolation or interpolation is applied using data

on the save grid, not the basic input grid (i.e., not the sparse grid). The extrapolation or

interpolation is specified by increasing the range of SLM and SLP in the path section.

Precise calculation of the transmission coefficients through the adiabatic barrier for

reactions involving two reactant or product species often requires calculation of the

ground-state (G) adiabatic energy

 

VaG (s) at large absolute values of the reaction

coordinate. But calculation of the MEP at large |s| is often impractical, especially in the

asymptotic regions near reactants or products, where a very small gradient step size is

often required for good accuracy because of the small magnitude of the gradient. To

alleviate this problem, the program contains an option to calculate

 

VaG (s) and

 

meff (s) at

large |s| by a two-point extrapolation method, controlled by the EXFIRST and EXSECOND

keywords in the PATH Section of the fu5 input when the hooks are used and the

NOSADDLE keyword is specified in the PATH section. This two-point extrapolation can

only be used for reactions without a saddle point or with electronic structure input files

fu30 and fu40. See the above discussion for more details. Here we discuss the method in

terms of

 

VaG (s), but the functional form is the same for

 

meff (s). [A similar extrapolation

is also made for

 

VMEP(s) but this is for informational purposes only, e.g., it may be

useful for plotting.]

The method used for bimolecular reactions when the calculation is based on a potential

energy surface involves a simple exponential function which is fit to the values of

 

VaG (s)

at the positive (s = SLP) or negative (s = SLM) limits of the reaction coordinate for which

 

VaG (s) has been accurately determined and to the adiabatic ground-state energies of the

products,

 

VaG (s = +¥) or reactants,

 

VaG (s = -¥). Thus

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VaG (s) = Va

G (s = +¥) + VaG (SLP) -Va

G (s = +¥)[ ]e-a(s-SLP)

for extrapolation towards products (s > SLP), and

 

VaG (s) = Va

G (s = -¥) + VaG (SLM) -Va

G (s = -¥)[ ]ea(s-SLM)

for extrapolation towards reactants (s < SLM). The exponential range parameter is

supplied by the user, or the default (1.0

 

a0-1) can be used. Different values of can be

used in the same calculation for extrapolations towards products and reactants.

If the keyword EXFIRST and EXSECOND are not specified, or EXNSTP is zero, no

extrapolation is performed. This is equivalent to using a = ¥, i.e., this is equivalent to

setting

 

VaG (s) equal to its value at s = SLP for all s > SLP and to its value at s = SLM for all

s < SLM.

As far as inputting a value of , the user may use any method he or she likes to get .

One suggestion for guesstimating is a 2-point fit of the exponential on to the end of the

Hessian grid data: Let sx be a point near SLP (sx could be the second-to-last point, or

slightly farther back if precision of

 

VaG (s) info is lacking). Then require exponential to

fit VaG(s = sx ) and V sa

GSLP( )= , which gives

 

a =ln Va

G s = sx( ) -VaG s = +¥( )[ ]{ / Va

G s = SLP( ) -VaG s = +¥( )[ ]}

SLP - sx( )

However, if the value chosen for affects the results, then this represents the basic

uncertainty in the values; a wider range for

 

VaG (s) will be needed to obtain a better

estimation of .

10.B. Options for anharmonicity

In addition to the standard harmonic option, several anharmonic options are available

using the keywords SSTOR, TOR, MORSE, MORSEQQ, MORMODEL, QQWKB, QQSEMI, and

WKB. Anharmonicity may be included in reactants, products, or generalized transition

states, but only in conjunction with the independent-normal-mode (INM) approximation

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in rectilinear coordinates except the SSTOR option. Two of these options, Morse I and

Morse I quadratic-quartic (MORSE and MORSEQQ respectively with the MORMODEL

variable keyword set to morsei), are described in the GTST book chapter (see pp. 87-92

of Ref. 5 in Sect. 21) and were first used in the calculations reported in Ref. 1 of Sect. 21.

The options defined by the QQSEMI and QQWKB keywords are two WKB options that will

be discussed in Subsection 10.B.1. The VARIABLE and VRANGE keyword options allow a

different anharmonicity method to be used for each mode in each region of the MEP.

When any of the above anharmonicity options are used, anharmonicity is computed for

all vibrational levels of a given mode by the same method. An additional anharmonic

option, specified by the WKB keyword, allows one to use a presumably more accurate, but

more time consuming method (the WKB method based on the true potential along each

generalized normal mode) for the ground-state energy level of each mode for modes

treated thermally, or for the specified energy level for state-selected modes. When this

option is chosen, the methods used for higher-energy states of thermal modes are still

determined by an additional anharmonicity keyword. If another anharmonicity keyword

is not included the higher-energy states will be determined using the harmonic

approximation. Details of the implementation of the WKB keyword option will be

discussed in Subsection 10.B.2. All WKB anharmonicity options are available only for

calculations based on the hooks. Whenever the WKB approximation is used, it is

employed in rectillinear coordinates, even if internal coordinates are used for the

frequencies and for non-WKB energy levels in the partition functions.

10.B.1. WKB anharmonicity based on a quadratic-quartic fit

When either QQWKB or QQSEMI keywords is specified, the program uses the primitive or

uniform WKB method, respectively, to compute the energy levels of a given generalized

normal mode vibration from a quadratic-quartic potential fit to the true potential. The

quadratic-quartic potential is determined by fitting to the potential computed at two

distances, specified by the user in the mass-scaled coordinate system, along the

generalized normal mode. The energy levels of this potential can be computed by either

a primitive WKB method [Ref. 21, Sect. 22] (QQWKB) or, for double well potentials, by a

semiclassical method using parabolic connection formulas [Ref. 22, Sect 20] (QQSEMI).

In these methods the phase integrals are calculated analytically. The calculations are

described in Ref. 17 of Sect. 21.

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10.B.2. WKB anharmonicity based on the true potential

When the WKB keyword is specified, the program uses the WKB method to compute the

anharmonic ground- or first-excited-state energy levels of all generalized normal mode

vibrations from the true potential along the modes. The method is described in more

detail in Ref. 13 of Sect. 21. Note that WKB energy levels are not computed for reactant

and product diatomic species, but instead either harmonic or anharmonic energy levels

(as specified by the other anharmonicity options) are used.

Because the numerical solution of WKB eigenvalues requires repeated calculation of the

potential and may therefore be quite time consuming, this approach is used only for the

zero point (n = 0) eigenvalues for thermal modes or the specified energy level for state-

selected modes. Higher energy vibrational levels, used in the calculation of the partition

functions, are obtained by harmonic or anharmonic approximations discussed previously.

In particular, when the WKB-with-the-true-potential option is applied to evaluate the

ground-state energy levels, the vibrational partition function of a bound motion is

calculated as follows:

 

Qvib,m = e-e

0,mWKB /kT

+ e- n+1/2( ) wm /kT

n=1

¥

å

 

Qvib,m = Qvib,mHO - e- wm /2kT + e

-e0,mWKB /kT

where e0,mWKB is the WKB ground-state energy of mode m, and Q mvib

HO, is the vibrational

partition function in the harmonic oscillator approximation. If the harmonic frequency is

imaginary, the partition function is set to 1010. Note that in the WKB method the turning

points are determined during the calculation of the vibrational energies, and they can be

used directly in the calculation of the effective reduced mass as a function of s.

This method is used in the test runs oh3tr3, ohcltr2, ohcltr3, and ohcltr4.

10.B.3. Hindered rotor treatments

Torsions may be treated multi-conformer methods as explained in Refs. 53 and 63 or by

multi-structural methods that couple the torsions as explained in Refs. 89, 90, 92–96, 98–

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105, and 113 of Sect. 21. These references explain the methods in detail, and they also

give original references. Note that we now recommend using MS-VTST or MP-VTST

rather than using the multi-conformer methods.

Beginning with version 8.2 of Polyrate, a torsional mode can be treated in the full

generality of Ref. 53. Please note the errata that have been added to Ref. 53. We label the

method developed in Ref. 53 as the Chuang-Truhlar (CT) method.

Beginning with version 2010 of Polyrate, several methods in Ref. 63 are also

implemented. These additional methods are the reference Pitzer-Gwinn (RPG) method,

the segmented- reference Pitzer-Gwinn (SRPG) method, the Ayala-Schlegel (AS)

method, and the segmented Ayala-Schlegel (SAS) method.

Beginning with version 2016, Polyrate can treat the torsional anharmonicity along

reaction path (saddle point and nonstationary points) by using coupled torsional

potentials in the multistructural method including torsional anharmonicity (MS-T(C)).

Note that only a single structure (SS) version is taken into account since only one saddle

point is given in a single Polyrate input file. Therefore we call this the SS-T method.

Multistructural (MS) effects should be taken into account separately by using the MSTOR

program.

There are two kinds of hindered rotor treatments: multiconformer (MC) methods and

multistructure (MS) methods. The MC methods involve identifying one or more of the

normal modes (or generalized normal modes) as a torsion about of specified bond. When

frequencies are required in MC methods they are normal-mode frequencies. The MS

methods do not require associating specific torsion with specific normal modes. When

torsional frequencies are required in MS methods, they are calculated in internal

coordinates based on a coupled model potential. In Polyrate calculations, only one

structure of the transition state or one reaction path is taken into account; therefore only

single-structure torsional potential anharmonicity (SS-T) along the reaction path is taken

into account.

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10.B.3.a. Multiconformer methods

10.B.3.a.i. CT method

If mode m is treated as a hindered rotor (HR) by the CT method, its partition function

tends to the limit of a harmonic oscillator ( HOmQ ) at low temperature and goes to the limit

of a free rotor ( FRmQ ) at high temperature, and the interpolation is designed so that it

remains reasonably accurate for the hindered-rotor regime between these limiting cases.

The CT method is:

 

QmHR = Qm

MC-HO tanhQm

FR

QmI

æ

è ç

ö

ø ÷ ,

where the multiconformer harmonic oscillator (MC-HO) approximation for mode m is

 

QmMC-HO, the free rotor approximation for mode m is

 

QmFR, and I

mQ is an intermediate

result. They are given by

 

QtorMC-HO =

e-b (U j + wtor, j / 2)

1- e-b wtor, jj=1

P

å

QFR =(2pIkT)1/2

s

QI =e-bU j

bw tor, jj=1

P

å

where P is number of distinguishable minima along the torsion coordinate, is (kBT)-1,

kB is Boltzmann constant, Uj is the energy of the jth well relative to the global minimum,

tor,j is the torsional frequency of the jth well along the normal-mode or generalized-

normal-mode coordinate, I is the averaged torsional moment of inertia of the P minima,

is the total symmetry number ( = M/P, M is the total number of minima along the

torsion coordinate in the range [0, 2)). Note that usually P = 1 or P = M. Therefore, if

M/P is not an integer, the program prints an error message and stops. The CT method

approximates the one-dimensional hindered-rotator problem with a simple model

potential of the form

 

V =W

2(1- cos Mf)

where W is the height of the potential barrier, and is a coordinate that parameterizes the

internal rotational motion. For a potential of the above form with a geometry-independent

moment of inertia, the barrier height Wj, moment of inertia Ij, and one-dimensional

torsional frequency tor,j are interrelated by

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wtor, j = MW j

2I j

æ

è ç

ö

ø ÷

1/2

If the frequencies tor,j are approximated as the same for all of the P minima and the

energies Uj are approximated as 0 (same as the global minimum energy) for all of the P

minima, we label this as single-frequency-and-energy (SFE) approximation. If only the

frequency is approximated as the same for all the distinguishable minima, we label it as

the single-frequency (SF) approximation. Otherwise, the treatment is labeled FULL.

Note that the single-conformer (SC) approximation in Ref. 52 is another name for the

special case of P =1. Therefore, starting from version 2010 of Polyrate program, this SC

approximation is not used as a stand-alone method.

10.B.3.a.ii RPG method

The torsional Pitzer–Gwinn method based on a reference potential gives the torsional

partition function as

 

QtorRPG =

1

P

QtorHO(wtor, j )

QtorCHO(wtor, j )

j=1

P

å QFR exp(-bW /2) I0(bW /2)

where

 

wtor, j is the frequency at the well j, W is the averaged barrier height of all the

wells to their left and right maxima, and

 

I0 is a modified Bessel function. If one uses the

frequency associated with the minimum of the 1D torsional reference potential to

approximate all the

 

wtor, j, this equation reduces to the Eq. 24 in Ref. 62. The reader is

referred to Ref. 62 for all further details.

10.B.3.a.iii. AS method

AS method uses a correction factor to adjust the RPG method

 

QtorAS =

1+ P2 exp[-bW /2]

1+ P1 exp[-bW /2]Qtor

RPG

where P1 and P2 are fifth order polynomial functions of

 

x º1/QFRand

 

y º bW /2 which

is given by Eq. 31 and 32 in Ref. 62.

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10.B.3.a.iv. SRPG method

If the hindered-rotator potential does not closely resemble the form of

 

V =W

2(1- cos Mf), it may be convenient to decompose the partition function into a sum

of contributions from particular wells and to fit the potential between each peak and

minimum using a simple cosine line shape. For each well, the contribution may be

divided into the part to the left of the minimum and the part to the right of the minimum,

and each part of the classical partition function may be evaluated analytically. This is

referred as the segmented-reference classical (SRC) approximation, and it yields

 

QSRC = Q jSRC

j=1

P

å

where

 

Q jSRC = exp(-bU j )Q j

FR

´(f j - f j

L )

2pexp(-bW j

L /2)I0(bW jL /2) +

(f jR - f j )

2pexp(-bW j

R /2)I0(bW jR /2)

é

ë

ê ê

ù

û

ú ú

where Uj is the energy of the local minimum centered at j relative to the energy at the

global minimum,

 

W jL and

 

W jR are the left and right barrier heights located at

 

f jL and

 

f jR, respectively, and

 

Q jFR =

2pI jkT

s

Quantum effects may be approximated by the Pitzer-Gwinn approximation to yield the

segmented-reference Pitzer-Gwinn method

 

QtorSRPG =

Q jHO(wtor, j )

Q jCHO(wtor, j )

j=1

P

å Q jSRC

10.B.3.a.v. SAS method

The AS method has a segmented approach that is analogous to the SRPG method, and we

refer to this analog to the segmented Ayala-Schlegel (SAS) method, in which each

occurrence of

 

exp(-bW j /2) in the SRPG method is replaced by a term like

 

exp(-bW j /2)1+ P2(I j ,W j )exp(-bW j /2)

1+ P1(I j ,W j )exp(-bW j /2)

where P1 and P2 are given by Eq. 31 and 32 in Ref. 62.

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The test runs ch4ohtr1, ch4ohtr3, ch4ohtr4, cwmctr2, cwmctr3, and h3o2fu31tr1 are

examples of using the hindered rotor options.

10.B.3.b. MS-T method

Starting from version 2016 of POLYRATE, the torsional-potential anharmonicity along the

MEP can be calculated using the MS-T method with a coupled torsion potential (i.e., MS-

T(C)), but only the input single transition structure is considered as generalized transition

states in the rate constant calculation; this is the SS-T treatment, i.e. Polyrate used by

itself does not compute the Multipath VTST (MP-VTST) rate constant, which requires

multiple transition structures in order to compute the variational and transmission

coefficients that correspond to their MEPs. Note that reactants and products are still

treated by harmonic oscillator approximation. To obtain rate constants calculated by the

full MS-T partition functions for reactants, products, and GTS, as well as the MP-VTST

rate constant, the user has to use MSTOR program (which is a separate program) to

calculate the rate constants at the conventional transition state and then use the variational

effects (ratio of CVT rate to TST rate) and transmission coefficients calculated by

Polyrate program (see the MSTOR manual for more details).

The conformational-rovibrational partition function using the MS-T method for a species

with J conformational structures is

Qcon-rovibMS-T = Q j

T j=1

J

å

QjT º Qrot, j exp -bU j( )Qj

QHTj

where Q jT

is the contribution of structure j to the rovibrational partition function with

torsional anharmonicity, Qrot, j is the classical rotational partition function for structure j,

U j is its relative potential energy, Q jQH

is its QH vibrational partition function partition

function, and Tj is a factor to account torsional-potential anharmonicity for all torsional

modes in the structure j. In particular, Tj is

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Tj = 2p b( )t/2

w j,mm=1

F

Õ

w j,mm=1

F-t

Õ

detD j

M j,tt =1

t

Õ

exp(-bWj,h / 2)I0(bWj,h / 2)h=1

t

Õ

where t is number of torsional modes, F is number of bound vibrational modes (stretches,

bends, and torsions), w j,m and w j,m are respectively the normal mode harmonic

frequencies and the torsion-projected normal mode frequencies (both sets scaled), D j is

the moment of inertia matrix of Kilpatrick and Pitzer, M j,t is the periodicity of torsion

in structure j, Wj,h is the torsional barrier height based on a coupled torsional potential,

and I0 is a modified Bessel function. Note that for nonstationary points along a reaction

path j (starting from the saddle point j), the vibrational mode along reaction coordinate is

projected out and the torsional-potential anharmonicity Tj is calculated for each

nonstationary points where Hessian is calculated or available. Therefore, vibrational

partition functions of points along reaction path includes the torsional-potential

anharmonicity and then torsional-potential anharmonicity is taken into account for

searching variational transition state.

To calculate Tj , one only needs to input the set of M j,t values for torsions and projected

frequencies have to be calculated using non-redundant internal coordinates.

10.C. Alternate method for the calculation of numerical second derivatives

In order to calculate the Hessian matrix, the second derivatives of the potential with

respect to the Cartesian coordinates are computed numerically, using the analytic first

derivatives supplied by the analytic potential energy surface subprogram. By default, the

method of central differences is used to compute these second derivatives. The formula

is given by equation (16) in the GTST book chapter (Ref. 5 of Sect. 21).

Two alternate options, selected by setting the NUMTYP variable keyword to quadratic

or fourth, were added for use in cases where the default method may lead to numerical

instability. In the most accurate option, NUMTYP = fourth, the second derivatives are

computed by fitting the analytic first derivatives to a fourth order polynomial. For

NUMTYP = quadratic, the second derivatives are computed from a quadratic fit of the

potential.

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The parameters NUMSTEP and DLX2, which are specified by the variable keywords

NUMSTEP and DLX2 respectively, in the input file which is linked to the FORTRAN unit

fu5, determine the step size for calculating second derivatives of the potential, and, if

needed, for cubic and quartic force constants as well. The second derivatives are needed

for two purposes: locating stationary points and computing vibrational potentials.

The DLX2 parameter is used for locating the stationary point, and the NUMSTEP parameter

is used for calculating the force constants. When anharmonicity options are chosen that

require cubic and quartic force constants, which are third and fourth derivatives of the

potential, these are evaluated as numerical second and third derivatives, respectively, of

the analytic gradient. The step size used for these numerical derivatives is always

NUMSTEP.

10.D. Reaction-path following methods

Our recommendations, as described in Ref. 27 of Sect. 21, for the most appropriate

methods for calculating the MEP and the reaction-path information required for

variational transition state theory calculations with semiclassical transmission coefficients

are as follows: (i) the Page-McIver algorithm, with the Hessian recalculated at every step,

and with a cubic starting step, (ii) the ES1* algorithm (the ES1 method with DELTA2 =

SSTEP and DIFFD = 0.01) with a Hessian step size three times larger than the gradient step

size, and with a quadratic starting step, and (iii) the Euler steepest-descents (ESD)

algorithm with a Hessian step size nine times larger than the gradient step size, and with a

quadratic starting step. The RPM keyword in the PATH section allows the user to choose

between the above possibilities or to choose other methods for computing the MEP. A

list of all methods available in this version is as follows:

The RPM keyword is set to esd for the ESD method. This method is discussed further in

Ref. 18 of Sect. 21.

The RPM keyword is set es1 for the ES1 method of Ref. 18 of Sect. 21. This is an

improved version of the methods proposed by Ishida et al. [Ref. 19, Sect. 22] and by

Schmidt, Gordon, and Dupuis [Ref. 20, Sect. 22]. The ES1 method allows for a user-

selected criterion for whether or not a stabilization is carried out.

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The RPM keyword is set to pagem for the Page-McIver method, which is called the local

quadratic approximation (LQA) in the original reference [Ref. 17, Sect. 22], for

calculating the MEP.

The RPM keyword is set to vrpe for the VRP method based on the Euler steepest-

descents algorithm for the zero-order step, which is called VRP(ESD). This method is

discussed further in Ref 49 of Sect. 21.

The ESD, ES1, and Page-McIver methods can be used with the RODS algorithm [Ref.

47, Sect. 21], to reorient the generalized-transition-state-theory dividing surface. This is

done by adding the RODS keyword in the PATH section of file fu5. The RODS algorithm

is not recommended for use with the VRP(ESD) algorithm since the generalized-

transition-state-theory dividing surface has already been optimized by the VRP(ESD)

algorithm.

Each of the above methods can be used with either a quadratic first step (i.e., a first step

along the imaginary-frequency normal mode) or a cubic starting algorithm in which the

first step off the saddle point is based on a cubic expansion of the potential energy surface

using the imaginary-frequency normal mode eigenvector and the curvature vector. This

is specified by the FIRSTSTEP variable keyword also in the PATH section. For a quadratic

first step set FIRSTSTEP = nmode and for a cubic first step set the variable to cubic.

A discussion of the above methods and useful hints for choosing the most appropriate

one, especially for direct dynamics calculations, is given in Ref. 27 of Sect. 21.

We use the following conventions for the step size of the save grid. The save grid is

defined as the set of points where the frequencies are stored for straight VTST runs, these

are also the points where the Hessian matrix is calculated and where generalized

transition-state normal mode analyses are performed and saved. The INH keyword

determines how many gradient steps are taken before a Hessian is calculated or read in.

In other words, the step size of the save grid is required to be an integer multiple, INH, of

the gradient grid step size. Hence, the save grid step size = INH SSTEP.

There is another option, which is specified by the SFIRST keyword, in which the first

NFSTEP steps are taken with a different gradient step size FSIZE. Then the gradient step

size, SSTEP, is used for the remaining steps.

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10.E. Interpolation of small-curvature effective reduced mass

For the small-curvature tunneling calculations (SCT), the effective reduced mass is

needed. The default method for computing the effective reduced mass from the values

stored on the Hessian grid, which includes s = 0, is spline interpolation. An alternate

method, selected using the LAGRANGE keyword within the SCTOPT list of the TUNNEL

section of the input is Lagrangian interpolation of order n. This new method is

recommended when using medium-to-large Hessian grid step sizes for which spline fits

tend to oscillate. The step size used for either of the interpolation methods is INH SSTEP

specified by the user with the SSTEP and INH keyword in the input data file. The alternate

method is used in the sample runs described in Subsections 16.C.3, 16.C.9, and 16.C.29.

10.F. Reaction-path curvature calculation

See Section 6.H for a brief introduction to reaction-path curvature.

When the CURV variable keyword in the PATH section of the input is set to oneside or

dgrad, the calculation of the component BmF(s) of the reaction-path curvature along the

direction of mode m at a point s on the reaction path Hessian grid, is carried out by eq.

(98) of the GTST book chapter. (This is equivalent to the second form of eq. (47) of [Ref.

17, Sect. 22].) This method requires the computation of the derivative of the gradient of

the potential with respect to the reaction coordinate s (see pages 96-98 in the GTST book

chapter). In early versions of the polyatomic VTST code this derivative was computed

using one-sided forward differences; see eq. (105) of the GTST book chapter. An option,

CURV = dgrad has been added to use a more accurate method, namely, central

differences (which is equivalent to a 3-point quadratic fit). When this new option was

added the one-sided difference method was changed to one-sided backward differences to

allow for a more consistent set of algorithms. It is recommended, however, that the

method of backward differences, CURV = oneside, never be used. The step size used

for these numerical derivatives is that of the gradient grid, SSTEP.

Another option, CURV = dhess, calculates the reaction-path curvature components using

eq. (48) of Page and McIver [Ref. 17, Sect. 22]. This method does not require the

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derivative of the gradient. A sample run with this option is discussed in Subsection

16.C.4. Preliminary tests indicated somewhat higher accuracy with dgrad.

For any of these choices of CURV, the code does not compute the curvature at s = 0

directly. Instead, the curvature at s = 0 is computed linear interpolation as described by

the INTMU keyword in the PATH section.

10.G. Solid-state and gas-solid interface reactions

A solid-state reaction, which includes gas-solid interface reactions as a special case, is a

reaction in which N primary atoms are considered to move in the presence of a fixed

solid. This is called the embedded cluster model; see Ref. 9 of Sect. 21. For solid-state

reactions, the SPECIES should be ssrp or ssts as explained in section 6.B.

10.H. VTST-IOC calculation, including ICR, ICL, and ICA schemes

The original VTST-IOC method is the VTST-IOC method that is described in Ref. 36 of

Sect. 21, and the modified version that was the default in Polyrate from version 7.2 –

7.9.2 is described in Ref. 44 of Sect. 21. In this manual we use the phrase VTST-IC to

refer to any scheme involving interpolated corrections from a higher level and VTST-

IOC to refer to any VTST-IC scheme in which the data for corrections involves a higher-

level optimization. Thus VTST-IC and VTST-IOC can involve not only the original ICA

scheme of Ref. 36 of Sect. 21 for interpolating corrections to frequencies but also to the

ICR and ICL options described in Ref. 44 of Sect. 21 and also described toward the end

of this section. To use any IOC method, the user has to prepare an input file (unit fu50;

see Subsection 12.F) which contains the necessary higher-level information. The DL

keyword must be set equal to ioc and/or the ICOPT keyword must also be given in the

GENERAL section of the unit fu5 input file.

If the MEP is finite (unimolecular reaction with a single product) or semi-infinite

(unimolecular reaction with two products or bimolecular reaction with a single product)

or has wells (i.e., precursor and/or successor complexes) that the user wishes to use in the

interpolation (i.e., if MEPTYPER or MEPTYPEP is (or both are set to well), the user has to

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tell the program where the MEP ends and/or some properties of the complexes

corresponding to the wells (see Subsection 12.F).

The VTST-IOC method demands an explicit matching of the frequencies, i.e., the user

must indicate which mode at the saddle point corresponds to each mode at the other two

stationary points involved in the interpolation (or else accept the default as explained

later in this paragraph). For a bimolecular reaction with two products (MEPTYPER and

MEPTYPEP are both set to two), the recommended method is to let the program match the

frequencies in descending order (which is the default in the current version), i.e., the

highest frequency at the saddle point is matched to the highest frequency of either of the

two asymptotic species, and so on. If the user knows (by symmetry and/or by inspecting

the uncorrected MEP output) that the matching should not be done in descending order,

then the user can use the FREQMAT keyword to input the matching order manually in unit

fu50. When MEPTYPER and MEPTYPEP are not both set to two, one of the normal modes

at the reactants and/or products turns into the reaction coordinate motion, and the user has

to specify the frequency matching explicitly, so the FREQMAT keyword must be used.

If a well is used for interpolation on the product side of the MEP, and the user is not

interested in the reverse rate constant, then the accurate product information is not

required. The user can use the NOPRODFREQ keyword to tell the program that no

correction for the product frequencies is needed. Otherwise the user has to use the

PRODFREQ keyword to input the corrected frequencies for the product in unit fu50.

The original IOC method involved the ICA option, which corrects all the frequencies, and

sometimes it will generate a negative correction that changes a small real frequency into a

negative frequency (not an imaginary frequency). In order to prevent this unphysical

result, one may use IVTST-0 for one or more low frequencies, or, preferably, one may

use one of two new interpolated correction options, namely the ICL (Interpolated

Correction based on Logarithm of ratios) and the ICR (Interpolated Correction based on

Ratios) options.

We note that all three IOC interpolation options for frequencies correct the lower-level

frequencies only when they are real. If the lower-level frequencies are imaginary, the

program does nothing, so the frequencies remain imaginary. (The recommended way to

handle this situation is to use the LOWFREQ option in the fu50 file. This option treats

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selected low-frequency vibrations by IVTST-0, while carrying out the rest of the

calculation by the VTST-IOC method.)

The differences between the original ICA option and the ICL and ICR options are best

illustrated by equations. Let

 

wmLL(s), m = 1, 2, ..., F-1 (where

 

F = 3N -6 for an N-atom

nonlinear generalized transition state) denote the lower-level frequencies of the

generalized transition state at s. In the original IC method, which is called “interpolated

corrections–additive” (ICA), the dual-level (DL) frequencies are given by

 

wmDL(s) = wm

LL(s) + f ICA(s)

where

 

f ICA(s) = interpolant wmHL(s) -wm

LL(s){ }s=-¥,0,¥

.

The “interpolated corrections based on the ratio” (ICR) and “interpolated corrections

based on the logarithm” (ICL) methods are defined by

 

wmDL(s) = wm

LL(s) f ICR(s)

where

 

f ICR(s) = interpolant wmHL(s) /wm

LL (s){ }s=-¥,0,¥

and

 

wmDL(s) = wm

LL(s)exp f ICL(s)[ ]

where

 

f ICL(s) = interpolant ln wmHL(s) /wm

LL(s)[ ]{ }s=-¥,0,¥

.

There are also options for interpolating V sMEP ( ) . The original option, called SECKART,

is described in Ref. 36 of Sect. 21. In the DECKART option, the dual-level V sMEP ( ) is

defined as:

 

VMEPDL (s) = VMEP

LL (s) + VEckHL(s) -VEck

LL (s)[ ]

where

 

VEck (s) =AY

1+ Y+

BY

(1+ Y)2+ C

 

Y = exps - S0

L

æ

è ç

ö

ø ÷

 

A =VMEP(s = +¥) -VMEP(s = -¥)

 

C =VMEP(s = -¥)

 

B = (2V¹ - A - 2C) ± (V¹ - C)(V¹ - A - C) ;

we choose

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S0 = -L lnA + B

B - A

æ

è ç

ö

ø ÷

so that the maximum of

 

VEck (s)occurs at s = 0.

 

V ¹is the classical barrier height, and L is

the range parameter. In

 

VEckHL(s), L is determined from the imaginary frequency of the

higher-level calculation by the equation

 

LHL =2V ¹(V ¹ - A)

m(w¹)2B

where µ is the scaling mass (normally set to 1.0 amu), and w¹

is the imaginary frequency

at the higher level. In VEck

LL(s), L is determined from a four-point fit to V sMEP ( ) at

reactants, products, saddle point, and one extra point as discussed in Refs. 36 and 44 in

Sect. 21.

Versions 7.2 – 7.9.2 used the so-called improved scheme (i.e. icl for vibrations and

deckart for V sMEP ( ) ) as the default VTST-IOC method. Beginning with version 8.0

the defaults are icl and seckart. To perform the calculation by the original IOC

method, a combination of ica and seckart was required. The Eckart function fit to 3

stationary points and

 

w¹ at the higher level can only be used for bimolecular reactions.

The following table summarizes the IOC options for interpolating corrections to

vibrations an to the VMEP curve:

Option no. Keywords

1 ica, seckart

2 icl, deckart

3 icl, seckart

4 icr, seckart

5 ica, deckart

6 icr, deckart

Option 1 was the original default, option 2 was the recommended choice and default in

versions 7.3 – 7.9.2, and option 3 is the current recommended choice and default.

In order to perform VTST-IOC calculations using any of the ica, icl, or icr choices

for interpolating vibrational information, we suggest the following procedure for a

bimolecular reaction:

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Step 1. Calculate the rate constants at the lower level. At the end of the reaction path

section in the long output file (i.e. before the reaction rate calculation), the

range parameter L is calculated automatically from a four-point fit. In the

same section, an L value obtained from the imaginary frequency at the lower

level is also calculated, but this is only for comparison.

Step 2. Input the range parameter L calculated from the four-point fit as the value for

the RPL keyword in the fu50 input file. Or calculate the range parameter L for

the RPL keyword in the fu50 input file with the findl.f program in /util. (See

Sect. 15.D.) This utility program asks the user to input the

 

VMEP values at

reactants, saddle point, and products (0, barrier height, endoergicity) and the

(s,

 

VMEP) values of an extra point which lies somewhere between s = – and

s = 0 (between the reactants and saddle point).

Step 3. Use the RESTART keyword to calculate the rate constants from the interpolated

corrections with the higher-level information given in fu50. (Note: The

RESTART option is not working properly in this version, you must do the

lower-level calculations again if you are dealing with an analytic surface.)

For a unimolecular reaction, the B parameter can be calculated from the findb.f program

in /util.

10.I. VTST-ISPE calculation

The VTST-ISPE method for calculating reaction rates is a dual-level approach. ISPE

denotes that the higher-level information consists of interpolated single-point energies.

The fully converged reaction path is calculated at a lower level of theory Y, e.g.

MP2/6-31G, and single-point energies are calculated at a higher level of theory X, e.g.

CCSD(T)/cc-pVDZ, where the geometry for the single-point calculation is taken from

level Y, denoted X//Y. In order to circumvent the limitation of the VTST-IOC formulas

that are designed for calculations in which only corrections at stationary points are used,

the VTST-ISPE calculations use the mapped interpolation formulas rather than the

VTST-IOC formulas. However, whereas the IVTST-M method requires at least one

nonstationary point on both sides of the saddle point, VTST-ISPE can handle the case

where corrected energies are provided only at one nonstationary point on either side of

the saddle point.

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To calculate the reaction rates with the VTST-ISPE algorithm, one should calculate a

converged reaction path at the lower level Y. Then a spline under tension is used to

interpolate the energy difference of a few single-point level-X energies along the level-Y

MEP and the energy from the lower level Y (i.e., V VX/ /Y Y- ). As in our previous

interpolated variational transition state theory with mapping (IVTST-M) method, a

mapping function is used to provide a systematic interpolating procedure for both

bimolecular and the unimolecular reaction. Like IVTST-M, which does not support LCT

calculations at this time, VTST-ISPE supports only ZCT and SCT tunneling options at

this time.

To map the reaction coordinate s into the z space, the following expression is used:

÷ø

öçè

æ -

p=

L

ssz 0arctan

2 (1)

Information from the lower level is used to obtain the parameters s0 and L for the

mapping. First we calculate

RWR,X;)()0(

2

XMEPMEP0

A =mw

-=-=

¹

sVsVs (2)

and

PWP,X;)()0(

2

XMEPMEP0

B =mw

-==

¹

sVsVs (3)

where m is the scaling mass, is the imaginary frequency of the saddle point at the

lower level, and R, RW, P, and PW denote the reactants, the reactant well, the products,

and the product well at the lower level. Then we calculate

( )0

B

0

AA 2,min sss -= (4)

and

( )0

B

0

AB ,2min sss -= (5)

Finally, the parameters s0 and L are obtained as:

2

BA0

sss

+= (6)

and

2

BA ssL

+-= (7)

The parameters s0 and L obtained from equations (5) and (6) are used in equation (1) to

map the reaction coordinate s into z. For a unimolecular reaction with a unimolecular

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product (A → B), where the reaction coordinate s occupies a finite interval, this maps a

finite interval in s into a finite interval in z. For a bimolecular reaction with bimolecular

products (A + B → C + D), where the s variable occupies interval [-, ], the mapped z

values are located in the finite interval [-1, 1]. For A → B + C or A +B → C, equation

(1) maps a semi-infinite interval of s to a finite interval of z. In all cases, a spline fit to

the differences of the classical energies is applied with this finite range of z. Therefore,

we can write the interpolated energy along the reaction path at the dual level as:

V V V zDL LL spline= + ( , )D (8)

where DL means dual level (VTST-ISPE), and LL means the lower level. V is the

difference of the classical energies between higher-level and lower-level at a particular s

value.

In the current version of POLYRATE, ISPE calculations may be used with the ZCT and

SCT tunneling methods but not with LCT or OMT.

To carry out a VTST-ISPE calculation, an external file fu51 is used to input the values of

the higher-level energies. Please refer to Section 12.G for a description of fu51. The

VTST-ISPE method can be applied with higher-level calculations at only the reactants,

products, and saddle point, or it may be applied with more points. In the latter case, extra

points are used to correct the energies along the MEP, the POINT sections are required for

the extra points.

The interpolation can be carried with or without the wells along the MEP. It is

recommended to use the well option if there is a complex along the MEP in order to

obtain the best interpolation. For bimolecular reactions, the energies of the saddle point,

wells, products, and extra points that are input via fu50 should be with respect to the sum

of the energies of the reactants at the higher-level (which is set to zero). There are two

test runs using the VTST-ISPE method, the ch5fu51tr1 test run which is a bimolecular

reaction with the J1 surface, and the cmctr3 test run, which is a unimolecular reaction

with two wells. For both reactions, we use the two turning points at the representative

energy of the SCT calculation at 300 K as the extra points, and we evaluate the single-

point energies with the MP2/6-31G** method.

The VTST-ISPE method can be applied for a minimum of three high-level points, namely

the reactants, saddle point, and products. The calculations are performed using unit fu51

with the stationary points being required in the ISPEGEN section of unit fu51, and the

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POINT section being included if and only if additional points along the reaction path are

added. A POINT section is needed for each additional high-level point along the reaction

path.

See Ref. 51 of Sect. 21 for more discussion.

10.J. Alternative methods for mapped interpolation

The mapped interpolation (MI) methods for IVTST-M calculations and for extrapolation

beyond SLM and SLP are described in Ref. 48 of Sec. 21. In addition to the standard

methods described in that paper, Polyrate contains a few variants that may be used to test

sensitivity to the approximations made in interpolation.

The first variant concerns the interpolation of VMEP(s) when there is only one reactant or

product or when interpolation is based on a well. The default is to use a cubic

polynomial in s to fill in 10 points between the end of the grid and the finite-distance

stationary point. Variant 1, with the nopolys option for the IVTSTMOPT keyword in the

PATH section of the fu5 input file, replaces the 10 points that in the standard algorithm are

calculated from a local cubic polynomial by a single point located a small distance (s)

from the reactant (or product or well), whose energy is approximated using the lowest

frequency at the stationary point. Thus the spline under tension is fit to 14 + m or 5 + m

points rather than 23 + m points. (See Ref. 48 for the definitions of m and other details.)

The second variant allowed in MI calculations is an alternative way to calculate the

effective reduced mass for CD-SCSAG calculations. The standard way involves

interpolating each curvature component. The alternative method, keyword INTMUEFF in

the GENERAL section of the fu31 input file, involves interpolating the argument of the

exponential function in eq. (16) of Ref. 48 instead of interpolating curvature components.

When the INTMUEFF keyword is used in conjunction with a VTST-IOC calculation, no

higher-level correction to μSC(s) will be made. The INTMUEFF keyword is only available

when using unit fu31.

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10.K. Quantized-reactant-state tunneling calculation

For unimolecular reactions at low temperatures, most of the reactant molecules have their

reaction-coordinate generalized vibrational modes in the ground state. Thus the

semiclassical treatment, which assumes continuous tunneling energies, is inappropriate.

Starting in version 6.2, we have included a new method that performs the tunneling

calculations only at the energies corresponding to the eigenstates of the reaction-

coordinate mode of the reactant for the case of a unimolecular reaction. (Note that all

other modes are still assumed to be in their ground states.) The reaction-coordinate

eigenstates can be determined using the harmonic or WKB approximation. Details of the

theoretical background and an application to the diffusion of hydrogen atoms on a Ni

surface can be found in Ref. 37 in Sect. 21. The keywords used to perform this type of

tunneling calculation can be specified in the TUNNEL section in the unit fu5 input file.

See Section 12.A.8 under the keyword QRST for details.

10.L. Curvilinear generalized normal mode analysis

The generalized normal mode analysis that is performed at each Hessian grid point (see

Section 9.C) on the MEP may be carried out either in Cartesian coordinates or in internal

coordinates. The COORD variable keyword in the PATH section makes it possible to select

the type of coordinates to be used. The default option for the COORD variable keyword is

cart which specifies Cartesian coordinates. (It is very important to use curvilinear

coordinates rather than Cartesian coordinates for VTST calculations; Cartesian

coordinate will very likely yield imaginary frequencies along the reaction coordinate,

which will cause unphysical VTST results.) Two options are available to select a

generalized normal mode analysis in nonredundant curvilinear coordinates: curv1 and

curv2. If either of the curvilinear internal coordinate options is selected for COORD, the

Cartesian gradient vector G and force constant matrix F at the save point are first

transformed to the curvilinear internal gradient vector g and curvilinear internal force

constant matrix f using equations 30 and 31 in Ref. 37 of Sect. 22 or using equations 10

and 11 in Ref. 46 of Sect. 21.

When the option curv1 is selected, the method of Ref. 41 of Sect. 21 is used for the

generalized normal mode analysis. The option curv1 is only available for

nonredundant internal coordinates for reactions involving a total of three atoms, and it

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may be used whether or not the geometry along the reaction path is linear. When the

curv1 option is chosen, the curvilinear internal coordinates—two stretches and a

nondegenerate bend for nonlinear triatomics or two stretches and a degenerate bend for

linear triatomics—are automatically defined by the program. In this method, the B

matrix and C tensor are constructed using the difference Cartesian coordinate formulas

from Pariseau et al. [Ref. 38, Sect. 22] for the bond stretch and nonlinear valence bend

coordinates and from Hoy et al. [Ref. 39, Sect. 22] for the degenerate linear bend

coordinate. The difference Cartesian B matrix and C tensor are then transformed to

Cartesian coordinates.

When the option curv2 or curv3 is selected, the method of Ref. 43 or 46 of Sect. 21 is

used for generalized normal mode analysis. The options curv2 and curv3 can be used

for any number of atoms, but curv2 is used for nonredundant internal coordinates, and

curv3 is used for redundant ones. Note that stretch, nonlinear or linear bend, and

dihedral curvilinear internal coordinates are allowed for this method. (The extension to

linear bends was presented in Ref. 45 of Sect. 21.) When the curv2 option is chosen,

the user is required to define the curvilinear internal coordinates used for the curvilinear

generalized normal mode analysis via the INTDEF keyword. In this method the Cartesian

B matrix and C tensor are constructed by using explicit FORTRAN statements [Ref. 40,

Sect. 22] for the B matrix and C tensor derived by Challacombe and Cioslowski [Ref. 41,

Sect. 22], except for the linear bend case where the derivation is presented in Ref. 45 of

Sect 21. If the curvilinear internal coordinate is a doubly degenerate linear bend, a

symbol “=” is used to indicate the connections between atoms within the INTDEF

keyword.

Next, at a nonstationary point along the MEP, the curvilinear internal force constant

matrix f is projected as

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fp = 1-p(BuBT)[ ]f 1- (BuBT)p[ ],

where

 

p =ggT

gT(BuBT)g,

before applying the Wilson GF method [Ref. 36, Sect. 22] of vibrational analysis to

obtain frequencies and generalized normal modes. The matrix u is a (3N 3N) matrix

with the reciprocal of each inverse mass appearing three times for each atom on the

diagonal, and the matrix B is the Wilson B matrix.

If POTENTIAL = unit30 or unit40 (see Section 12.A.3), normal mode analyses at

stationary points are always carried out in Cartesian coordinates. If POTENTIAL = hooks,

normal mode analyses at minima are carried out in Cartesian coordinates, and the normal

mode analysis at the transition state is carried out in curvilinear coordinates. Note that

options for anharmonicity (e.g., TOR and MORSE keywords in Section 12.A.6) have not

been implemented for curvilinear internal coordinates. Therefore, keyword options

curv1, curv2 and curv3 should not be used with anharmonicity options.

At stationary points, one should obtain the same frequencies by using either curvilinear or

rectilinear coordinates, except for small differences due to round off. However at non-

stationary points the generalized normal mode frequencies do depend on the coordinate

system — see Refs. 25, 41, 43, 45, and 46 in Sect. 21. (It is very important to use

curvilinear coordinates rather than Cartesian coordinates for VTST calculations;

Cartesian coordinate will very likely yield imaginary frequencies along the reaction

coordinate, which will cause unphysical VTST results.)

In the current version, both curv1 and curv2 are restricted to use a nonredundant set

of internal coordinates. Redundant internal coordinates are always chosen by the option

curv3. In POLYRATE, the number of curvilinear internal coordinates cannot exceed 3N-6

for the curv1 and curv2 options. The option curv3 allows the number of internal

coordinates to be as large as 3N + 6.

10.M. IVTST0FREQ option

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In some cases, we found that the directly calculated frequencies of the lowest real-

frequency modes are not stable or not accurate along the reaction path, and this can cause

problems in evaluating the zero point energies, partition functions, and tunneling

probabilities. To ameliorate this problem, we have added a new scheme for interpolating

frequencies. This scheme is called IVTST−0-for-frequencies; it is a single-level analog

of the method used for interpolating differences of frequencies in the VTST-IC method

[Ref. 36, Sect. 21]. In the IVTST−0-for-frequencies scheme, the interpolation procedure

has one of four possible forms, depending on the molecularity of the end points of the

interpolation. Unimolecular reactions always have a molecularity of one at the negative s

terminus. Interpolations for bimolecular reactions may have molecularity two at the

negative s terminus, or − instead of extending all the way to reactants, the interpolation

may extend only to a reactant-side well where the molecularity is one. Similar

considerations apply on the product side.

MEP type 1. Bimolecular/bimolecular interpolation

A bimolecular/bimolecular interpolation is for a reaction that has two reactants and two

products. Either there are no wells present on either side of the reaction path or (more

likely) wells are present but are not used in the interpolation, i.e., they are not recognized.

There are two functional forms used for this case,

a. If )( Rww >¹ and )( Pww >¹

or if )( Rww <¹and )( Pww <¹

, where

)0( ==¹ smm ww , )( -¥== smR ww , and )( +¥== smP ww , an Eckart function is used

to approximate the frequencies along the reaction path:

mmm

m CY

YB

Y

YAs +

++

+=

2)1(1)(w (1)

where

)()( -¥=-+¥== ssA mmm ww (2)

 

Bm = (2wm¹ - Am - 2Cm) ± 2 (wm

¹ - Cm)(wm¹ - Am - Cm)[ ] (3)

)( -¥== sC mm w (4)

÷÷

ø

öçç

è

æ -=

L

SsY

m,0exp (5)

÷÷ø

öççè

æ

-

+-=

mm

mmm

AB

BALS ln,0 . (6)

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Unlike the original VTST-IC algorithm, we use a single-level analytical expression for

estimating the value of L instead of using a fit involving a lower level. The analytical

expression is [Ref. 26, Sect. 21]

B

AVVL

2

2

)(

)(2

¹

¹¹ --=

wm (7)

)()( MEPMEP -¥=-+¥== sVsVA (8)

)(MEP -¥== sVC (9)

 

B = (2V ¹ - A - 2C) ± 2 (V ¹ - C)(V ¹ - A - C)[ ] (10)

)0(MEP ==¹ sVV (11)

where MEPV is the potential energy along the reaction path, and ¹w is the imaginary

frequency at the saddle point.

b. If )( PR www >> ¹ or if )( PR www << ¹

, a hyperbolic tangent function is

used to approximate the frequencies along the reaction path:

mm

mm EL

TsAs +÷

÷

ø

öçç

è

æ -=

,0tanh

2

1)(w (12)

where

2

)()( -¥=++¥==

ssE mm

mww

(13)

÷÷ø

öççè

æ

-

+-=

m

mm

x

xLT

1

1ln

2,0 (14)

m

mmm

A

Ex

-=

¹w2 (15)

c. For cases where two consecutive of the three frequencies are the same (i.e.,

Rww =¹or Pww =¹

, a constant value or used at one side of the reaction path and a

symmetric Eckart function fit is used on the other. For example, if PR www ¹= ¹, then

îíì

>++

£=

0)1/(

0)( 2

R

sYYB

ss

mPm

w

ww (16)

where

)(2)2( PP wwww -±-= ¹¹mmmB (17)

÷ø

öçè

æ=

L

sY exp (18)

and L2 is given by eqs. (7)−(11).

MEP type 2. Two reactants to one product (or well)

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We introduce the notation P−W which denotes the product or the well, whichever is

being used as the right-side edge of the interpolation region. In this type of reaction the

function used to fit the frequencies depends on the s value, which is in the range of

WP-<<¥- ss .

a. If s < 0, a hyperbolic tangent function is used to approximate the frequencies as

described in the previous section for base 1b.

b. If WP0 -££ ss , a cut-off hyperbolic tangent is used to approximate the

frequencies:

mm

mm Ess

s

L

TsAs +

÷÷

ø

ö

çç

è

æ

÷÷ø

öççè

æ

-

-=

-

-

WP

WP,0tanh

2

1)(w (19)

where mA , mT ,0 , and mE are the same as previous section. L is evaluated using eqs.

(7)−(11). This makes )(smw continuous with one continuous derivative.

If ¹= mm ww R, or WP, -¹ = mm ww , then the value of R,mw or W- P,mw is modified by ± 2

cm−1 to make the function monotonic.

MEP type 3. One reactant (or well) to two products

This type of reaction is similar to type II but the functional forms are reflected

through s = 0.

MEP type 4. One reactant (or well) to one product (or well)

We introduce the notation R−W which denotes the reactant or the reactant-side well,

whichever is being used as the left-side edge of the interpolation region.

a. If )( W-Rww >¹ and )( W-Pww >¹ or if )( W-Rww <¹ and )( W-Pww <¹ , two

cut-off Gaussian functions are used to approximate the frequencies along the reaction

path:

xm

x

xmxmm C

s

s

BAs ,2

,,

1

exp)( +

÷÷÷÷÷÷

ø

ö

çççççç

è

æ

÷÷ø

öççè

æ-

-=w ; x = R-W,P-W (20)

)exp()( ,, xmxmxm BA ww -= ¹ ; x = R-W,P-W (21)

xxmC w=, ; x = R-W,P-W. (22)

The parameter xmB , is evaluated using a single-level analytical expression rather than a

fit to a lower-level surface. In particular we use

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Bm,x =sx2m w¹( )

2

2 V ¹ -Vx( ); (23)

b. If ¹= mm ww W-R, or ¹= mm ww W-P, then the frequency is set equal to a constant

on one side of the saddle and approximated by a symmetrical cut-off Gaussian is used for

the other side on the reaction path. For example, if WP,W-R, -¹ ¹= mmm www , then the

frequency is set to W-Rw when 0£s and evaluated using eqns. (20−23) when s > 0.

c. If )( W-PW-R www >> ¹ or if )( W-PW-R www << ¹ , a cut-off hyperbolic

tangent function is used to approximate the frequencies along the reaction path.

mm

mm Ess

s

ss

s

L

TsAs +

úúû

ù

êêë

é

÷÷

ø

ö

çç

è

æ

-÷÷ø

öççè

æ

-

-=

-

-

-

-

WR

WR

WP

WP,0tanh

2

1)(w (24)

where mA , mT ,0 , and mE are determined by eqns. (2,13−16), and L is evaluated using eq.

(7).

The keyword option IVTST0FREQ is used to apply the IVTST0FREQ method for

interpolating the vibrational frequencies along the path. If either side of the reaction path

is unimolecular or if one recognizes an intermediate structure (indicated by *WELLR or

*WELLP sections), then an arc distance from saddle point has to be provided for the

interpolation (by using the SR and SP keyword options).

The equations in this section are not currently published; the only available reference is

this manual.

10.N. LCG4 option

Beginning with version 8.6, the options LCT3 and LCT4 are both available, but one cannot

use both of them in the same run. These two options replace the previous LCT option.

The LCTOPT keyword includes four new options.

The option vadavg can be used with LCT3 or LCT4, and it averages the vibrationally

adiabatic potential in a doubly vibrationally adiabatic region. Specifically,

 

Veff (x) = VeffIII(˜ s 0,xI) +

x -xIII

xI -xIIIVeff

I (˜ s 0,xI) -VeffIII(˜ s 0,xIII)[ ]

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where III and I indicate the beginning and end of the region that overlaps. The default

is novadavg and the vibrational adiabatic potential in this region is given by

 

Veff (x) = min VeffIII(˜ s 0,xIII),Veff

I (˜ s 0,xI)[ ]

The option vefsrch numb only can be used with the LCT4 option, and it switches on

the search for nonadiabatic regions that are completely adiabatic in the LCT3 method. In

particular, it becomes operative at the tunneling energy after (higher than) that for which

the last nonadiabatic region was found according to the LCG3 algorithm, and the search

is carried out for a total of numb energies beginning at that point. The search locates the

maximum of the vibrationally adiabatic potential at a given tunneling energy and

compares the value with the actual potential. If the actual potential is smaller than the

adiabatic potential, then the procedure ends, otherwise the nonadiabatic region is

extended until the vibrationally adiabatic potential is smaller than the actual potential.

The default is vefsrch 999 because this search is required for correct LCG4

calculations. There is also an option called novefsrch that is equivalent to vefsrch

O.

For example, if 80 linear paths are calculated, and the 40 lowest-energy paths have

nonadiabatic regions in LCG3, setting numb equal to 20 will cause the program to search

for nonadiabatic regions along paths 41–60. This avoids the search for nonadiabatic

regions along the 20 highest-energy paths where it is likely that nonadiabatic regions may

exist only due to round-off; it allows one to avoid extra calculations at these energies

very close to the effective barrier top because they have no significant effect on the

results.

A restart option has been added, and it is described by two new keywords in LCTOPT. In

particular, lctstr stores the information in unit fu49 (this is the default), and

lctsrst restarts a calculation from unit poly.fu48. An old calculation stored in fu49

can be restored directly if fu49 is renamed as fu48. The default is nolctrst. If

lctrst is specified, but the unit poly.fu48 does not exist, the program stops

automatically. With lctrst the LCTOPT options have to be the same as in previous

calculations, that is, ngamp and ngtheta cannot be changed.

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To incorporate the restart option in Polyrate the modules were modified. The old LCG3

subroutine (renamed in version 8.5 as LCG) reads from unit fu48 and stores the

information in the common block LCRST1 which is linked to LCVEF.

This restart option will work in POLYRATE, MORATE, and GAUSSRATE. When the restart

option is used with GAUSSRATE, the restarting data for the LCT calculation will be read

from fu48 instead of esp.fu83.

This restarting procedure is simple and flexible, and it allows the use of an old LCG3

fu48 file to restart an LCG3 calculation or to start a new LCG4 calculation, or vice versa.

All the combinations are possible. The restart option is specially useful when we want to

calculate tunneling into vibrational accessible excited states. In a first run we can do the

calculation of the ground state large curvature transmission factor. This information is

saved in unit FU49. We can include tunneling into vibrationally excited final states in a

second run if still worth it after looking at the output.

Further details of the LCG4 algorithm are provided in Ref. 54 in Sect. 21.

10.O. MS-VTST, MP-VTST, FMS-VTST, and FMR-VSTT calculations by using

both the Polyrate and MSTOR programs

For molecules and transition states that have multiple conformations generated by

torsions, we recommend MS-VTST [61], MP-VTST [62,63,72], FMS-VTST [68], or

FMP-VTST [68] calculations. Such calculations can be carried out by making runs with

Polyrate and MSTOR programs. The MSTOR program [64-66] is a program for applying

the internal-coordinate torsional anharmonicity method [70,71,68] for treating torsional

anharmonicity (MS-T); it is available as a separate package at

http://comp.chem.umn.edu/mstor/.

The internal-coordinate torsional anharmonicity method is a practical thermochemical

method for including multiple structures and torsional anharmonicity to calculate

conformational–vibrational–rotational partition function for complex systems. This

scheme obviates the need of earlier approaches to identify torsional motions with specific

normal modes, and it approximately accounts for coupling of torsional modes to one

another and to other modes. It includes the conformational free energy associated with

the existence of multiple structures (conformations) and the additional effects of torsional

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potential anharmonicity. The original paper [70] included methods based on a subset of

structures as well as the method using all structures. The method containing all structures

was originally call MS-AS, but now we usually use all structures and, as explained in ref.

[64], we simply refer to the method employing all structures as MS-T.

In the original papers introducing MS-VTST [61] and MP-VTST [62,63,72], we

included multistructural torsional anharmonicity only at stationary points; tunneling

transmission coefficients and recrossing transmission coefficients were calculated in the

quasiharmonic (QH) approximation. (A quasiharmonic calculation is one that uses the

harmonic oscillator formulas for vibrational partition functions but with effective (scaled)

frequencies rather than the harmonic frequencies; the effective frequencies are usually

chosen to improve the estimate of the zero point energy [69].) In Ref. [68] we introduced

the capability to include multistructural anharmonicity all along the reaction path. To be

precise, we will label calculations by the original methods as MS-VTST [61] and MP-

VTST, and we will label calculations with multistructural anharmonicity all along the

reaction path [68] as full MS-VTST (FMS-VTST) and full MP-VTST (FMP-VTST).

In carrying out MS-VTST and MP-VTST calculations, Polyrate is used to carry

out single-structure quasiharmonic (SS-QH) calculations for reaction paths. In carrying

out FMS-VTST and FMP-VTST calculations, Polyrate is used to carry out single-

structure quasiharmonic what we shall call single-structure torsion (SS-T) calculations.

Throughout this discussion, we use the word structure as a synonym for conformation.

An SS calculation involves a single conformational structure of each reactant and a single

conformational structure of the transition state. SS-QH calculations use the QH

approximation along the reaction path, and SS-T calculations use the MS-T

approximation along the reaction path.

A note about chirality: when one is carrying out a single-structure calculation to

compare with experiment, if the structure has a distinguishable mirror image, then one

needs to include an extra factor of two in its rate constant, as discussed elsewhere [67].

However, in this section, we literally mean a single structure and the factor of two is not

included in such a case.

Some preliminaries about notation: (1) When we say "variational effects" we

mean the difference between a variational transition state theory calculation and a

conventional transition state theory calculation. In MS-VTST, MP-VTST, FMS-VTST,

and FMP-VTST calculations, variational effects are included by multiplying a

conventional transition state theory rate constant by a transmission coefficient that is

called a recrossing transmission coefficient. (2) The methods explained here may be used

with a variety of approximations for the tunneling, for example, ZCT, SCT, LCT, OMT,

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or LAT. In general we use the abbreviation MT ("multidimensional tunneling") to refer to

any of these. (3) In our original paper

This subsection explains how to perform MS-VTST, MP-VTST, FMS-VTST, and

FMP-VTST calculations by combining results from Polyrate and MSTOR. In brief, the

MSTOR program is used to perform all the calculations for the stationary points (reactants,

saddle points, and products), and Polyrate is used to perform SS-QH or SS-MP reaction

path calculations to obtain variational effects and transmission coefficients.

In order to carry our either an MS-VTST or an MP-VTST calculation, the first

step is to find all the conformational structures of the transition state (that is, all the

saddle points leading from reactants to products along parallel reaction paths (as

contrasted to reaction paths in series)) and all the structures of the reactant or reactants.

Structures of the transition state are called transition structures, and structures of the

reactant(s) are called reactant equilibrium structures or just reactant structures. Next one

numbers the transition structures so that the lowest-energy one is called k =1, and in

another list one orders the reactant equilibrium structures so that the lowest-energy one is

called k = 1. The energy difference between the lowest-energy transition structure and the

lowest-energy reactant equilibrium structure is called the classical barrier height, V‡ .

Then one uses MSTOR to calculate MS-T partitions functions for the transition

state and the reactant(s). For the reactant of a unimolecular reaction, this partition

function is called QMS-T, R . For the reactants of a bimolecular reaction, the product of

the partition functions of the two reactants ( QR1 and QR2 ) is also called Q

MS-T, R , but

the quantity we will need to calculate rate constants in the bimolecular case is F (the

partition function per unit volume) rather than Q (the partition function) so that one has to

convert Q to F when calculating bimolecular rate constants. Note also that it is possible

that MS-T will be used for only one of the two reactants. If the reactant R2 does not have

torsion, then one may use a simpler method, for example, the harmonic or quasiharmonic

approximation, for QR2

. Then FMS-T, R

is the bimolecular reactants’ partition function

per unit volume (with its zero of energy at the sum of the potential energies of the lowest-

energy reactant structures), and QMS-T, R

is the total partition function of a unimolecular

reactant (with its zero of energy at the potential energy of the lowest-energy reactant

structure).

The partition function for the transition state is called QMS-T,‡

. Note that this

partition function is sum over contributions from distinguishable structures:

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QMS-T,‡

= QkT,‡

k=1

K

å (1)

where K is the number of distinguishable conformational structures of the transition state,

and QkT, ‡

is the rovibrational partition function of saddle point k with torsional potential

anharmonicity (T). Note that the difference in energy between the zero of energy used for

the transition state partition functions QkT,‡

and that used for the reactant partition

function is taken here to be the classical barrier height, which is the potential energy of

the lowest-energy conformational structure (k = 1) of the saddle point minus the potential

energy of the lowest-energy equilibrium structure of the reactant.

The next step is to perform one or more SS calculations with POLYRATE; this is

explained next.

10.O.1. MS-VTST

The MS-VTST rate constants including multidimensional tunneling are given by

the following formulas for a bimolecular reaction and a unimolecular reaction

respectively:

kbimolMS-CVT/MT = k1

QHG1QH-CVT kBT

h

Qelec‡ Qk

T,‡

k=1

K

å

FMS-T, R

exp(-bV‡) (2)

kunimolMS-CVT/MT = k1

QHG1QH-CVT kBT

h

Qelec‡ Q

kT,‡

k=1

K

å

QMS-T, R

exp(-bV‡) (3)

where k1QH is the quasiharmonic tunneling transmission coefficient for the reaction path

passing through transition structure 1, b is 1/ kBT , kB is Boltzmann’s constant, T is

temperature, h is Planck’s constant, Qelec‡ is the electronic partition function of the

conventional transition state (which is denoted as ‡); and the CVT recrossing

transmission coefficient for structure 1 is G1QH-CVT , which is given by the ratio of the

quasiharmonic CVT rate constant for the reaction path through transition structure 1 to

the quasiharmonic conventional TST one for transition structure 1.

In order to obtain k1QH and G1

QH-CVT , one performs an SS-QH calculation with

POLYRATE. The k1QH is printed out in the Polyrate output file and G1

QH-CVT is calculated

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G1QH-CVT =

k(1),QH-CVT

k(1),QH-TST (4)

10.O.2. FMS-VTST

An FMS-VTST calculation is the same as an MS-VTST one except for the

transmission coefficients. One replaces k1QH and G1

QH-CVT by k1T and G1

T-CVT , which

are obtained by running SS-T calculations in Polyrate with the keyword SSTOR. In

particular, the recrossing transmission coefficient G1T-CVT is calculated as

G1T-CVT =

k(1),T-CVT

k(1),T-TST (5)

10.O.3. MP-VTST

In MP-VTST, we calculate the transmission coefficient as a properly weighted

average over tunneling transmission coefficients and variational transmission coefficients

for several reaction paths instead of calculating transmission coefficients only from one

path as is done in MS-VTST. This subsection gives the procedure to perform MP-VTST

calculations.

The MP-VTST rate constants including multidimensional tunneling are given by

the following formulas for a bimolecular reaction and a unimolecular reaction

respectively:

kbimolMP-CVT/MT =

kBT

h

Qelec‡

FMS-T, R

exp(-bV‡) kkQH G

kQH-CVT Q

kT,‡

k=1

K

å

» gkBT

h

Qelec‡ Qk

T,‡

k=1

K

å

FMS-T, R

exp(-bV‡)

(6)

kunimolMP-CVT/MT » g

kBT

h

Qelec‡ Q

kT,‡

k=1

K

å

QMS-T, R

exp(-bV‡)

(7)

where the MP-VTST generalized transmission coefficient is approximated by

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g =

kkQH Gk

QH-CVT QkT,‡

k=1

P

å

QkT,‡

k=1

P

å

(8)

To evaluate the quantities in these formulas, we have to make P runs of Polyrate (where

P ≤ K), one for each of the P user-selected distinguishable structures of the transition

state (note that these structures are numbered by k = 1, ..., P). Each of the runs gives a

quasiharmonic CVT rate constant k(k ),QH-CVT , a quasiharmonic conventional TST rate

constant k(k ),QH-TST, a quasiharmonic tunneling transmission coefficient kkQH , and a

quasiharmonic CVT recrossing transmission coefficient GkQH-CVT . The first three are

printed in the Polyrate output file, and the fourth is given by

GkQH-CVT =

k (k ),QH-CVT

k (k ),QH-TST

(9)

The other quantities needed for MP-VTST rate constants can be calculated by using the

MSTOR program.

Note also that GkCVT is independent of which reactant structure is used, but the

choice of reactant structure affects the lower-energy limit of the integration used to

calculate kk , and thus it could affect the values calculated for the rate constants at low

temperature. Therefore all the additional Polyrate runs (k = 2, ..., P) needed to upgrade

MS-VTST to MP-VTST should use structure k of the transition state and the lowest-

energy structure of the reactant(s). Note that one has to calculate a reaction path long

enough to make sure the kk is converged. In case the saddle point k is connected with a

reactant(s) conformation much higher in energy than the lowest-energy structure of the

reactant(s), there is possibilities that the kk is overestimated because of the program is

trying to integrate kk to the lowest-energy structure of the reactant(s). This is one aspect

if the calculation that needs to monitored carefully if calculations are made at low

temperature.

Note that the wavy equal sign in equation (6) can be replaced by a straight equal

sign if P equals K. When P = 1, the MP-VTST rate reduces to the MS-VTST rate.

Alternatively one also can calculate the MP-VTST rate constants by the following

procedure. Let’s define the multistructural torsional anharmonicity factors for reactants

(R1 and R2 for bimolecular reactions, R1 = R for unimolecular reactions) and for saddle

point 1 (lowest-energy saddle point) as

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FR1 =QMS-T,R1

Q1QH, R1

(10)

FR2 =QMS-T,R2

Q1QH, R2

(11)

F‡, 1 =QMS-T,‡

Q1QH, ‡

(12)

Then we obtain the MP-VTST rate constants as

kbimolMP-CVT/MT = g

F‡,1

FR1FR2k

bimol(1), QH-TST

(13)

kunimolMP-CVT/MT = g

F‡,1

FR1k

unimol(1),QH-TST

(14)

10.O.4. FMP-VTST

An FMP-VTST calculation is the same as an MP-VTST one except for the

transmission coefficients. One replaces kkQH and Gk

QH-CVT by kkT and Gk

T-CVT in

equation (8); these quantities are obtained by running SS-T calculations in Polyrate with

the keyword SSTOR. In particular, the recrossing transmission coefficient GkT-CVT is

calculated as

GkT-CVT =

k(k),T-CVT

k(k),T-TST (15)

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Part III Theory Background for VRC-VTST

11. THEORETICAL BACKGROUND ON VRC-VTST

For an association reaction without a barrier or with a negligible barrier, we recommend

using the multifaceted (MF) extension of variable-reaction-coordinate variational

transition state theory (VRC-VTST) . The references for VRC-VTST is Y. Georgievskii

and S. J. Klippenstein, J. Chem. Phys. 2003, 118, 5442, and the reference for the

extension of VRC-VTST to use MF dividing surfaces is Y. Georgievskii and S. J.

Klippenstein, J. Phys. Chem. A 2003, 107, 9776.

In VRC-VTST, the reaction coordinate and dividing surfaces are defined in a different

way than in RP-VTST. In VRC-VTST, the reaction coordinate s is defined by the

distance between a pivot point on one reactant and that on another, and the dividing

surfaces are defined in terms of pivot points tied to each of the reactants. Choices of the

number and location of these pivot points yield different definitions of the reaction

coordinates and hence of the generalized transition state theory dividing surfaces, and

reactive flux is variationally minimized with respect to both these choices and the

distance between pivot points in the two reactants. The original version of VRC-VTST

employed one pivot point on each reactant, and the MF extension involves two and more

pivot points on one or both reactants. In this manual we consider the use of MF dividing

surfaces to a special case of VRC-VTST. The evaluations of the reactive flux involves

Monte Carlo integration over the coordinate space degrees of freedom of the classical

phase space representation of the generalized transition state partition function for

arbitrary orientations of the reagents over a wide range of interfragment separations.

Because there is no saddle point for a barrierless association reaction, the conventional

TST rate is not calculated. The START section only needs the electronic degeneracy

information for electronic partition function calculations. Association rate constants can

be calculated by CVT, VT, or E,J -VT. Tunneling calculations cannot be performed

for this type of calculation.

11.A. Variable reaction coordinate

When a single-faceted dividing surface is used, the reaction coordinate s for a barrierless

association reaction is defined as the distance between two pivot points, one associated

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with each of the two reactants. Since s is defined as a distance here, its value is always

positive. Thus, it has a different meaning from the s used in RP-VTST. The following

scheme shows the definition of the reaction coordinate s for the case of a single-faceted

dividing surface.

Here, the two ovals represent the two reactants. COM1 and COM2 are their centers of

mass. P1 and P2 are pivot points associated with reactant 1 and reactant 2, respectively.

d(1) and d(2) are vectors connecting a pivot point with its associated reactant’s center of

mass, respectively. When the distance s between two pivot points is fixed, the directions

of s, d(1), and d(2) are sampled over the whole phase space simultaneously. The lengths

of these vectors are fixed during the sampling over their orientations.

In the VRC-VTST approach, the modes of motion are divided into two sets, conserved

modes and transitional modes. The conserved modes correspond to the vibrational modes

of the two reactants. In the complex of two reactants, these modes usually correspond to

the modes with highest vibrational frequencies. VRC-VTST, at least in its present state of

development, assumes that changes of conserved modes are negligible during the reaction

process. The transitional modes include the other vibrational modes except conserved

modes in the complex and the overall rotations. These modes change from free rotation

and translation at infinite separation of the reactants to vibrational motion and overall

rotation during the reaction process. The new vibrational modes are very floppy and are

best thought of as liberations.

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The high-pressure limit rate constant for the generalized transition state at location s

along the reaction coordinate and at the temperature T can be expressed as

 

k(T,s) =2

2pge

s1s2

s‡Q1Q2

2p

mkBT

æ

è ç

ö

ø ÷

3

2dE e-E/kbT dJ N(E,J,s)ò (1)

where s is the value of reaction coordinate, which is defined above as the distance

between two pivot points; ge is the ratio of the electronic partition function of the

transition state to the product of the electronic partition functions of reactants; is the

reduced mass; Q1 and Q2 are the rotational partition functions of the reactants calculated

without symmetry numbers; J is the unitless total angular momentum quantum number;

N(E,J ,s) is the number of accessible states of the generalized transition state s for total

energy E and angular momentum Jħ; and σ1, σ2, and σ‡ are the rotational symmetry

numbers for the reactants and transition state, respectively.

The keyword SIGMAF in RATE section (see Section 13.A.6) is equal to σ1σ2/σ‡. For

reactions in which the two reactants are the same, SIGMAF is 0.5; for reactions in which

the two reactants are different, SIGMAF is 1.0. This is explained in the following

paragraph. As background for this explanation, we first note that eq. (137) in the review

by Bao and Truhlar1 is identical to eq. (4) in the PNAS paper by Bao et al.,2 although in

the PNAS paper we include the rotational symmetry factors in the reactant partition

functions, whereas in eq. (137) of the review we separated them. Note also that σ1 and σ2

should have their correct symmetry numbers as usual.

The next question is: What is σ‡? Georgievskii and Klippenstein3 (in their eq. 2) define

σ = σ1σ2/σ‡

and they make the assumption that – since the transition state is loose – there is free

rotation of both species, such that the transition state partition function contains the

product of the two rotational partition functions. Then

σ‡ = σ1σ2σadd

1 J. L. Bao and D. G. Truhlar, Variational Transition State Theory: Theoretical Framework and Recent Developments, Chem. Soc. Rev., 2017, 46, 7548-7596. doi.org/10.1039/C7CS00602K 2 J. L. Bao, X. Zhang and D. G. Truhlar, Association of CF2 and Dissociation of C2F4 by

Variational Transition State Theory and System-Specific Quantum RRK Theory, Proc. Natl.

Acad. Sci. U. S. A., 2016, 113, 13606. doi.org/10.1073/pnas.1616208113 3 Y. Georgievskii and S. J. Klippenstein, Long-range transition state theory, J. Chem. Phys.,

2005, 122, 194103. doi.org/ 10.1063/1.1899603

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where σadd is the additional symmetry gained in the transition state. Because we sample

all possible orientations (Euler angles) of the transition state classically in VRP-TST, we

must divide by two when the association reactants are identical because the phase space

may be divided into two quantum mechanically indistinguishable spaces when the two

reactants are identical. This means that σadd equals 1 if the species are different and equals

2 if they are the same. Therefore σ1σ2/σ‡ equals 1 if the species are different and equals

0.5 if they are the same. One could call this the loose-transition-state assumption for the

symmetry number of the transition state.

The number of accessible states for the transitional modes with total energy E and

angular momentum quantum number J can be written as

(2)

where denotes the average over all possible orientations of the two reactants and of

the orientation of the vector s; Q means a specific configuration of the system. Since this

multidimensional integral is carried out by Monte Carlo integration, the configurations of

the system are randomly sampled over the whole phase space corresponding to a given s.

In our implementation, one specific random configuration is determined by the following

procedure:

(1) P1 is always taken as the origin of the system for every random configuration.

(2) The position of P2 is determined by a random solid angle

(3)

where

 

xP2 is the Cartesian coordinate of pivot point P2; )( 12

1

12 −A is the inverse rotation

matrix,

 

A12-1 =

cosq12 cosf12 -sinf12 sinq12 cosf12

cosq12 sinf12 cosf12 sinq12 sinf12

-sinq12 0 cosq12

æ

è

ç ç ç

ö

ø

÷ ÷ ÷ (4)

(3) Since the Cartesian coordinates of P1 (

 

xP1) and P2 (

 

xP2 ) are known, the Cartesian

coordinates of the center of mass of the kth reactant (

 

xcomk) are given by

(5)

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(6)

where is the inverse rotation matrix, and is solid angle for the

kth reactant; )(kd is the length of vector )(kd .

(4) Since the internal geometries of the reactants are fixed at the input ones, and their

center of mass positions are determined in step 3, the coordinates of the generalized

transition states are simply obtained by a translation.

The quantity ),,,( sQJEN q can be loosely viewed as number of accessible states for a

specific configuration Q with total energy E and angular momentum Jħ, which can be

expressed as

, (7)

 

F = 1+ m n(12) ´d(k) ×ni(k)( )

i=1

vk

åk=1

2

å2

/Ii(k) , (8)

where denotes the averaging over all possible orientations of the vector of angular

momentum J while its length is fixed. In equation (7), is a kinematic factor given by

Equation (8);

 

v equals v1 + v2 + 3 where

 

vk (k = 1,2) is the dimensionality of the

orientational space for the kth reactant;

 

Ii(k) denotes the ith moment of inertia of the kth

reactant, and

 

Ii is the ith moment of inertia for the system as a whole;

 

n(12)is the unit

vector directed from the second pivot point to the first one;

 

d(k)is the vector connecting

the center of mass of the kth reactant to its pivot point;

 

ni(k) is the unit vector directed

along the ith principal axis of the kth reactant;

 

ka is the number of monatomic reactant,

which should be equal to 0 or 1.

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Although Equation (8) for the kinematic factor is valid for both linear and nonlinear

molecules, it is convenient to rewrite the term for linear molecule in a different form:

 

mI-1 (n(12) ´d ×ni

i=1

2

å )2 = mI-1 1- (n(12) ×n0)2[ ], (9)

where 0n is the unit vector directed along the axis of the molecule; I is the moment of

inertia.

There are three ways to perform variational calculations. They correspond to optimizing

the transition state dividing surface using three different ensembles. The resulting rate

constants are labeled canonical variational theory (CVT), microcanonical variational

theory (VT), and energy and total angular momentum resolved microcanonical

variational theory (E,J -VT), respectively. We now discuss these three choices:

(i) Energy and total angular momentum resolved microcanonical variational theory:

For E,J -VT theory, N(E,J ) is minimized with respect to s for each E and J. Then the

integral in Equation (1) is calculated using the optimized N(E,J ).

The minimum of the number of accessible states is obtained by interpolation from a

quadratic fit to N(E,J ,s) at the three values of s nearest to the minimum. We call this

method a 3-point fit; 3-point fits are also used in VT and CVT. The integrals over E and

J for the optimized N(E,J ) in Equation (1) are approximated by Gauss-Laguerre and

Simpson’s rule quadratures, respectively.

(ii) Microcanonical variational theory:

For microcanonical variational theory (VT), the integral over J in Equation (1) is carried

out first to get N(E,s). By integrating Equation (7) over J and substituting the result into

Equation (2), the number of accessible state N(E,s) is obtained as the following

expression:

(10)

Then N(E,s) is minimized with respect to s for each E, and the optimized N(E) is used for

the integral over E.

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(ii) Canonical variational theory:

For canonical variational theory (CVT), N(E,J ,s) is calculated for all E and J at a single

s value. Then the rate constants k(T,s) is minimized with respect to s for each T. The

analytic result of the integral in Equation (1) is expressed as:

(11)

11.B. Multifaceted dividing surface

When one uses single-faceted dividing surfaces, two pivot points (with one on each of the

associating reactants) and a fixed distance between them form a spherical dividing

surface. But in many cases the reactants of association reactions have multiple binding

sites. Multiple binding sites on one or both reactants require more pivot points to increase

the flexibility of the shape of the dividing surface. Let’s assume that n1 pivot points are

assigned to reactant 1 and n2 pivot points are assigned to reactant 2, and the reaction

coordinate value is s. Therefore there are

 

n1 ´ n2 pairs of pivot points. Each pair of pivot

points corresponds a sphere, and the points on each sphere are selected according to the

following condition to form a composite dividing surface:

 

mini=1, j=1

n1,n2ri, j = s (12)

where

 

ri, j is the distance between the ith and jth pivot points associated with the first and

the second reactant, respectively; s is the value of reaction coordinate. The meaning of

Equation (12) is that at one particular configuration of the complex at any of the spheres

formed by the

 

n1 ´ n2 pairs of pivot points, if the minimum of the distances between

pivot points associated with different reactants equal to the value of reaction coordinate,

this configuration will be accepted in Monte Carlo sampling. Therefore the composite

dividing surface has

 

n1 ´ n2 elementary surfaces; each of the elementary surfaces is

called a facet, and the composite surface is called a multifaceted (MF) dividing surface.

In variational calculations, various locations of pivot points should be considered to

minimize the reaction rate. Users are responsible to try various sets of locations of pivot

points; that is, Polyrate has not automated this. The optimal locations of pivot points are

the locations that minimize the reaction rate; but the user must be careful that the MF

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dividing surface defines by the chosen locations of the pivot points separates reactants

from products.

11.C. Overview of program flow for VRC-VTST calculation

When the VRC method is used for loose transition states by turning on the VRC

keyword in the GENERAL section, the program will not use the MEP as the reaction path,

but will instead use variable reaction coordinates and either single-faceted or multifaceted

dividing surfaces. After the MAIN program reads all the information provided at reactants,

subroutine VRCTST is called. Note that user gives the information about two reactants in

this case, and the START section only need the ELEC keyword for electronic degeneracy

information. If only the forward reaction rate constants for association need to be

calculated, the product information is not required. In VRC-VTST calculations, the MAIN

program and subroutine VRCTST are parallelized using MPI, and they work independently

on different processors to read the same fu5 input file and perform Monte Carlo

sampling. During the Monte Carlo sampling, only energies are calculated (for various

geometries along the reaction path), and gradients and Hessians are not required. When

the Monte Carlo sampling is finished on all processors, one processor (rank 0 in MPI) is

used to collect the data calculated on all the processors and to perform the rest of the

calculations to get reaction rate constants.

11.D. Implementation details of the E, J-resolved microcanonical VRC algorithm

This section contains material from the Supporting Information Appendix of ref. [75]

of Sect. 20.

We here describe the implementation details of the E,J-resolved microcanonical

VRC algorithm for the case of two pivot points on fragment 1 and two on fragments 2; the

generalization to a larger number of pivot points is straightforward. We denote the pivot

points on fragment 1 as point 1 and point 2 and the pivot points on fragment 2 as point 3

and point 4. The range of reaction coordinate s searched for a variational transition state is

from sl to su (“l” stands for lower edge of the range, and “u” stands for upper edge of the

range), and the search for a variational transition state is carried out by varying s with increments of size sstep.

We define the vector s as a vector connecting two pivot points, one in each fragment.

This is illustrated in Scheme S1, where we are considering a particular pair of pivot points,

namely pivot point 1 of fragment 1 and pivot point 3 of fragment 2, so we only show the

vector s that connects these two pivot points, and only these two pivot are shown (other

pivot points on fragments 1 and 2 are not shown).

In the computer code, we loop over the pairs of pivot points with one on each

fragment (1-3, 1-4, 2-3, 2-4), and for each pair of pivot points, the vector s is defined as

the vector that connects the pivot point on fragment 1 with the pivot point on fragment 2.

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The magnitude of s is denoted as s; this is the same as the reaction coordinate s mentioned

in the first paragraph.

Scheme S1

Step 1: Set the length of the reaction coordinate s to sl.

Step 2. Do for m from 1 to 4. For each m, we consider a pair of pivot points with

one on each fragment. Index m =1 corresponds to pair 1-3, m = 2 represents the pivot points

pair 1-4, m = 3 represents the pivot points pair 2-3, m = 4 represents the pivot points pair

2-4. For our explanation we will use m =1 as an example; in particular, m = 1 corresponds

to choosing pivot point 1 and pivot point 3. For case m = 1 or 2, P1 is pivot point 1, and for

m = 3 or 4, P1 is pivot point 2. For the case m = 1 or 3, P3 is pivot point 3; and for m = 2

or 4, P3 is pivot point 4.

Each performance of Step 2C-1 is a Monte Carlo sample. The number of Monte

Carlo samples per value of m is denoted as NMC, which is a number specified by the user,

and which is the same notation as used in the input and the code. That is, for each m, there

are NMC Monte Carlo samples. Because each pair of pivot points determines one facet of

the dividing surface, and we have four pairs (i.e., we have a four-faceted dividing surface),

the total number of Monte Carlo samples is 4NMC. In eq 12 of J. Phys. Chem. A 2003, 107,

9776, which will be used in Step 4, the variable M is equal to 4NMC.

Step 2A for this pair m: Put fragment 1 in a specific initial orientation (this starting

orientation is determined randomly) with respect to P1; set the vector s (as shown in

Scheme S1) in a specific initial direction (this direction is also determined randomly as a

start direction) so that P3 position has been decided; and then put the fragment 2 in a

specific initial orientation (this starting orientation is determined randomly) with respect

to P3. Therefore the coordinates of the whole system and other pivot points are determined.

Calculate the length of the vector RCOM that connects the centers of mass of the fragments.

Step 2B for this pair m: Do for i from (m – 1)NMC + 1 to (m – 1)NMC + NMC.

Starting from the initial configuration determined in Step 2A, we now start doing Monte

Carlo sampling, i.e., randomly orientating the two fragments, while keeping the length of

vector s as specified in Step 1. When orientating the fragments, P1 is always taken as the

origin of the coordinates system. Then, the position of P3 is determined by a random

solid angle. After reorienting s, also reorient fragment 2 (the solid angles for these

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reorientations are determined randomly). This now yields configuration i.

Step 2C for this i:

Step 2C–1: Fragment 1 has pivot points 1 and 2, and fragment 2 has pivot points 3

and 4, and the distances between each of the various pairs of pivot points (with one on each

fragment) can be computed. Compute the distance rij (where i = 1, 2, and j = 3, 4) for each

pair of pivot points (1-3, 1-4, 2-3, 2-4) for current Monte Carlo sample configuration. If

any of the four rij is greater than or equal to s (no matter which pair of the pivot points

satisfies this condition), then go to Step 2C-2, otherwise abandon this configuration. If this

configuration is abandoned, it does not count in ¢M in eq. 13 of J. Phys. Chem. A 2003,

107, 9776; if this configuration is accepted, then it increases the value of ¢M by 1.

Step 2C–2: For the specific configuration accepted in Step 2C-1, compute the

moment of inertia of each fragment and the unit vector along its principal axis; and

calculate the kinematic factor Φ (eq. 2.40 in J. Chem. Phys. 2003, 118, 5442). Next

compute number of states Nq(E,J,s,i) for this value of the reaction coordinate s and this

specific specific configuration i, and for each combination of total energy E and angular

momentum vector J (the length of which is denoted as J), averaged over all the possible

orientations of vector J while its length is fixed; this is eq 9 of J. Phys. Chem. A 2003, 107,

9776, and it is computed at using eq 2.39 in J. Chem. Phys. 2003, 118, 5442. Note that we

included the correction factor of 2 that is indicated in reference 12 of J. Phys. Chem. A

2003, 107, 9776.

Step 2D: If you have not yet done NMC samples for this m, go back to Step 2B,

except start with the present configuration rather than the initial one. If you have completed

this m, go to step 2E.

End do loop over index i.

Step 2E: If m is less than 4, increment m by 1 and carry out Steps 2A to 2D for the

next pair of pivot points.

End do loop over index m.

Step 3. Now compute the generalized transition state approximation (for a transition

state at reaction coordinate value s) of the number of states for the transitional modes at

total energy E and total angular momentum J. This is given by

NGT E, J, s( ) =1

MNq

i=1

¢M

å E, J, s, i( ) (13)

Step 4: If s < su, increase the length s of vector s by sstep, and go back to Step 1. After

all the values of s specified by the user have been considered, go to Step 5.

Step 5: In E,J-resolved microcanonical variational theory, for each E and J,

minimize N(E,J,s) with respect to s. This yields

NmVT E, J( ) = NGT E, J, s*( ) (14)

where s*

is the value of s that minimizes the number of states. Then plug NmVT E, J( )

into the rate constant expression and evaluate the integral to obtain the final rate constant

k(T).

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PART IV DESCRITION OF INPUT FILES

12. DESCRIPTION OF INPUT FOR RP-VTST

In the following subsections, a record-by-record description of the data for each input file

that is used for RP-VTST calculations is given:

Subsection 12.A: the input data needed from unit fu5;

Subsection 12.B: the input data needed from unit fu29;

Subsection 12.C: the input data needed from unit fu30;

Subsection 12.D: the input data needed from unit fu31;

Subsection 12.E: the input data needed from unit fu40;

Subsection 12.F: the input data needed from unit fu50;

Subsection 12.G: the input data needed from unit fu51.

12.A. General description of file fu5 input

The input for FORTRAN unit fu5 is of the free format keyword style. The fu5 input

consists of up to twelve sections. These are defined in sub-section 12.A.1. The input file

consists of section headers (section headers are always preceded by a star, *) and

associated keywords.

The keywords are of three types: switch, variable, and list. A switch keyword acts as a

toggle for an option. A switch keyword, for example SWITCHKEY, usually has an

associated form, for example NOSWITCHKEY, that causes the opposite action. A variable

keyword always requires an argument. These are usually used for parameters that have

to have a value, such as step sizes, convergence criteria, etc. The argument must appear

on the same line as the variable keyword. The third type is the list keyword. A list

keyword has one or more level-2 keywords associated with it; these keywords may be

switch or variable keywords, and the latter kind have arguments. The use of a list

keyword takes the form:

LEVEL1KEYWORD

LEVEL2KEYWORDA

LEVEL2KEYWORDB

...

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END

where the END line is mandatory.

All switch and variable keywords have default values, and these types of keywords need

be given only if the user wishes to override the default. Some, but not all, list keywords

have defaults as well. (Additional keywords, called level-2 keywords or subkeywords,

are associated with some list keywords — see above. Sometimes, but not always, level-2

keywords have defaults.) List keywords start a subsection that is always terminated with

an END line.

Except for the input of the TITLE keyword in the GENERAL section, all input is case

insensitive, and anything after a pound sign (#) on a line is assumed to be a comment.

Blank lines are ignored. It is highly recommended that the novice user print out one of

the test run input files and compare it with the descriptions in the following subsections.

A suggested file for this purpose is ch5j2tr3.dat. The rest of subsection 12.A details the

keywords for each of the twelve sections. Please note that every keyword must be used

in its proper section, i.e., between the occurrence of its starred header and the occurrence

of the next starred header (or, for the last section, between the proper starred header and

the end of the file).

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12.A.1. Section descriptions

The following input sections correspond to the major parts of a RP-VTST rate

calculation. Each section begins with a line giving the section name, preceded by an

“ * ”. An input file can contain all or some of these sections in any order except for a

restart calculation. For a restart calculation, the first section in the file must be the

GENERAL section and the REACT1, REACT2, PROD1, PROD2, WELLR, WELLP, START, and

PATH sections cannot be used. Keywords for each section are discussed further in the rest

of this subsection. For runs using the fu30, fu31, or fu40 electronic structure file input

options, one should not include sections SECOND or OPTIMIZATION.

Section Name Description

*GENERAL general data such as the title and defining the atoms involved

*ENERGETICS options for computing potential energy and first derivatives

*SECOND options for computing second derivatives

*OPTIMIZATION methods for performing geometry optimizations

*REACT1 definition and properties of the first reactant

*REACT2 definition and properties of the second reactant

*PROD1 definition and properties of the first product

*PROD2 definition and properties of the second product

*WELLR definition and properties of the reactant side well

*WELLP definition and properties of the product side well

*START definition and properties of the saddle pt. or starting geom.

*PATH options for computing the MEP

*TUNNEL options for computing the tunneling corrections

*RATE options for computing the reaction rate

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12.A.2. GENERAL section

The GENERAL section is used to give a title that can be used to identify the run, define all

the atoms in the reacting system, specify the potential energy surface or electronic

structure input option to be used, set up restart criteria (if applicable), and specify

whether IVTST-0, IVTST-1, VTST-IOC, or VTST-ISPE is to be used. (IVTST-0 can

also be specified on file fu50.) If this is a restart run then the first keyword given in this

section must be TITLE. It is good practice to always make this the first keyword so that

input files can be easily identified. The table below lists all the valid keywords for the

GENERAL section. Indented keywords are level-2 keywords, and the others are level-1

keywords. Level-2 keywords are always associated with a level-1 list keyword and must

come after that keyword and before any other level-1 keyword or starred header. In the

alphabetical glossary that follows a more complete explanation for each keyword is

given. In a standard run this section would have the TITLE and ATOMS keywords. Note

that ATOMS is a required keyword.

When using electronic structure input files, IVTST-M is on if and only if one uses file

fu31 or if one sets LOPT(2) = –1 in file fu30 or if one sets MAXLPTS = –1 in file fu40.

Otherwise IVTST-M is off, which means that any interpolation Polyrate needs to

perform to fill the save grid storage arrays is calculated by Lagrangian interpolation.

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Basic:

Keyword Type Default Description

TITLE list blank title with 5 lines maximum

ATOMS list required atoms in system

CHECK switch off check the input data

CLASSVIB switch off classical treatment of vibrations for vibrational partition function

DL variable none interpolated corrections

ICOPT list not used interpolated correction options

BOTH switch off based on corrected and uncorrected data

CORRECT switch on based on corrected data

ENERGY variable seckart Eckart function fit to VMEP(s)

FREQ variable icl interpolated correction of frequency

IVTST0 switch off zero-order IVTST

IVTST1 switch off first-order IVTST

INPUNIT variable angstrom specifies the units in fu5 input file

OUTUNIT variable angstrom specifies the units in fu6 and fu14 output files

MDMOVIE switch off write MDMOVIE input file

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Basic:

Keyword Type Default Description

RESTART list not used restart options

WRITEFU1 switch off write restart file on unit 1

READFU1 switch off read restart file from unit 1

READFU1&2 switch off read restart files from units 1&2

WRITEFU3 switch off read from 1&2, write to 3

MERGE variable 0 an option for merging MEPs

SUPERMOL switch on supermolecule mode for reactants and products

WRITE62 variable none write information in the fu62 file

WRITEFU30 switch off write an fu30 file

WRITEFU31 switch off write an fu31 file

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Glossary of GENERAL keywords

ATOMS

ATOMS is a required list keyword that is used to specify all the atoms in the system. For

each atom the user must specify n, a sequential number unique to each atom in the

molecule, and a label, either the atomic number or symbol of atom n. The mass of the

atom in atomic mass units (amu) can also be specified following the label. If it is not

included then the mass of the most prominent isotope is used. This program uses the

universal atomic mass scale, i.e., the mass of 12C is 12.000000. (For this scale, the

correct abbreviation is u, although most people use the old-fashioned abbreviation amu.)

The mass is supplied from an internally stored table using the atomic number or symbol

as given by the user. Note that the unique number n will be used in other sections to

specify the atom. The example below corresponds to monodeuterated water.

Example: ATOMS

1 O

2 H 1.0078

3 H 2.0140

END

CHECK

CHECK is a switch keyword that tells the program to stop immediately after checking the

input data files. It is especially useful to use this keyword before a long or complicated

calculation to make sure that all the data are input correctly. The default is off.

CLASSVIB (NOCLASSVIB)

CLASSVIB is a switch keyword that determines if the vibrational partition functions are to be calculated assuming a classical treatment of the vibrations. The default is that vibrations are treated as quantized. If CLASSVIB is used, all vibrational partition functions are calculated using the classical expression for harmonic oscillators; therefore, no anharmonicity should be specified for any modes.

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DL

DL is a variable keyword that determines if the dual-level interpolated corrections are

done. (See Subsection 10.H.) The default is none. See Section 12.F. This keyword can

also be used to perform IVTST-0 calculations with unit fu50; see Section 6.N. The valid

options are

Option Description ioc dual-level using fu50 (VTST-IOC)

ispe dual-level using fu51 (VTST-ISPE)

none dual-level calculation is not performed (default)

Example: DL ioc

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ICOPT

ICOPT is a list keyword that sets options for interpolated optimized corrections. If this

keyword is used, then it is assumed that VTST-IOC is desired, and the DL keyword is set

to ioc. Note that if neither icr nor ica is specified, the correction defaults to the ICL

method, and if energy deckart is not specified then the single Eckart function is

used. (This differs from versions 7.2 – 7.9.2 and earlier) The ICA, ICL, and ICR

schemes, and the two ways to use Eckart functions are discussed in section 10.H. The

valid options are given below.

Option Description Default

both separate calculations will be based on the corrected off

and uncorrected data

correct calculation will be based only on the corrected data on

energy interpolated optimized corrections for energies: seckart

deckart - difference of two Eckart functions fit to

the VMEP(s) curve at higher level and

Eckart function fit to lower level seckart - do not use Eckart function fit to the

VMEP(s) curve at higher level but rather

use a single Eckart fit to the difference

freq interpolated optimized corrections for frequencies: icl

ica - interpolated correction based on arithmetic

differences

icl - interpolated correction based on logarithm of

ratios

icr - interpolated correction based on ratios

none - no corrections

Example: ICOPT

ENERGY DECKART

FREQ ICA

BOTH

END

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INPUNIT

INPUNIT is a variable keyword that specifies the units for the geometries and distances

given in the fu5 input file. This keyword will have no effect on selecting the units for the

geometries and variables for distances in other input files (units fu29, fu30, fu31, fu40, or

fu50). The default is ang.

Option Description ang angstroms

au atomic units

Example: INPUNIT AU

IVTST0

IVTST1

IVTST0 and IVTST1 are switch keywords to turn on the zero- and first-order Interpolated

VTST (IVTST-0 and IVTST-1) calculations, respectively (See Subsection 6.N.). The

default is off.

MDMOVIE

MDMOVIE is a switch keyword that determines if an input file for MDMOVIE should be

written out. MDMOVIE is a visualization program that allows animation of motion of the

system along the MEP. The default is off.

OUTUNIT

OUTUNIT is a variable keyword that specifies the units for the geometries and distances

given in the fu6 and fu14 output file. The default is ang.

Option Description

ang angstroms

au atomic units

Example: OUTUNIT AU

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RESTART

RESTART is a list keyword that gives the user control over the restart capability of the run

or designates the current run as a restart calculation. See Section 7.C. for general

comments on this option. If this keyword is not used, a future calculation at a different

temperature must start from scratch. Alternatively a user can use the writefu1 option

within RESTART and the reaction path will be written to unit fu1. In future runs, the user would just need to specify the readfu1 option within RESTART for the same reaction

path to be read from unit fu1. All the valid options are given below. Note that merge

requires an argument specifying the increment value. The default is that this keyword is

not included, i.e. this is not a restart run and no restart file should be written.

Option Definition

writefu1 write restart information to unit fu1 for future use

readfu1 restart calculation using information on unit fu1

readfu1&2 restart calculation using merged MEP, MEP #1 on unit fu1 is

merged with MEP #2 on unit fu2 and the merged file is not

saved.

writefu3 the merged MEP from readfu1&2 is written to unit fu3

merge x increment in s to be added to the s values of MEP #2 when it is

merged with MEP #1. This is required if the READFU1&2 option

is used. The default unit is angstroms and it can also be in bohr

by specifying the keyword INPUNIT AU.

writefu30 write an fu30 file

writefu31 write an fu31 file

Example: RESTART

READFU1

END

NOTE: When writing an fu30 file (writefu30 option) the user needs to supply an

fu30 file with the necessary LOPT(1-40) options.

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SUPERMOL (NOSUPERMOL)

SUPERMOL is a switch keyword which indicates that the supermolecule mode is used for

reactants and products. The default for SUPERMOL in Polyrate is on. This keyword is used

only when the keyword POTENTIAL is set equal to hooks, and the choice has no effect if

there is only one reactant and one product. The use of supermolecule mode is most easily

explained by an example. Consider a bimolecular reaction with reactants A and B. For an

analytical potential energy function or a non-size-extensive electronic structure method, one

would usually calculate the energy of reactants by placing A at a distance of 20–100 ao from

B and calculating the energy of the AB supermolecule. However, for size-extensive methods

like Hartree-Fock and MP2, one would usually prefer to calculate the energies of A and B

separately and add them. The latter requires NOSUPERMOL.

For a bimolecular system, NOSUPERMOL causes Polyrate to calculate the zero of energy as the

sum of the potential energies of the two reactants using two separate calculations in which

each reactant is treated separately. This is not very useful with an analytical potential energy

surface. When NOSUPERMOL is specified, the geometries in REACT1 and REACT2 each contain

less than the full number of atoms. In the case of SUPERMOL, the first reactant is optimized

and its energy is calculated by having the second reactant frozen at a long distance (which is

specified through the definition of the geometries in section REACT2 in file fu5). Then the

second reactant is optimized with the first one already at its equilibrium geometry, but far

away, and the sum of their energies is obtained as the energy of the supermolecule

calculation, i.e., when SUPERMOL is on one does not add the energies from REACT1 and

REACT2 at the end of the calculation. The same considerations apply to PROD1 and PROD2 if

there are two products.

TITLE

TITLE is a list keyword that allows the user to give a title to the run. The user can specify

up to five lines of 80 characters each. Like all list variables, an end must be given at the

end of the TITLE subsection. This must be the first keyword list in the GENERAL section

for a restart calculation.

Example: TITLE

CH3 + H2 —> CH4 + H TEST RUN

ESD/HARMONIC

END

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WRITE62

WRITE62 is a variable keyword that determines if a subset of the stationary point

information from file fu61 should be printed in fu62 file. The default is none. The valid

options are

Option Description none no information is printed in fu62

viball frequencies (in cm–1) are printed for all stationary points

vibsp frequencies (in cm–1) are printed only for the saddle point

Example: write62 vibsp

WRITEFU30

WRITEFU30 is a switch keyword that determines if an output fu30 file should be written

out. Notice that the points are not in the required ascending order. Therefore the points

in the created fu30 file need to be reordered by the user before using the file. The default

is off.

WRITEFU31

WRUTEFU31 is a switch keyword that determines if an output fu31 file should be written

out. The written file is ready to use with the unit31 option for the POTENTIAL keyword

in the ENERGETICS section of the fu5 input file. The options for writing the fu31 file

cannot be selected. It will always be written in atomic units, and the program will always

write unscaled gradients and packed Hessians in the fu31 file.

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12.A.3. ENERGETICS section

The ENERGETICS section is used to define the method for computing the potential energy

of the reacting system and the corresponding first derivatives. The table below lists all

the valid keywords for the ENERGETICS section. In the alphabetical glossary that follows

a more complete explanation for each keyword is given.

Keyword Type Default Description

EZERO variable calculate method for determining zero of E

EZUNIT variable a.u. units of zero of energy

POTENTIAL variable hooks type of PES to be used

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Glossary of ENERGETICS keywords

EZERO

EZERO is a variable keyword specifying how the zero of energy should be determined.

This keyword is discussed briefly in detail in Section 8.B. Polyrate always sets the zero

of energy equal to the energy of the reactants, which is defined to be the sum of the

energies of both reactants for a bimolecular reaction or to be the energy of the single

reactant for a unimolecular reaction. However, the other option is to read in the zero of

energy with option read #. The default is calculate.

Option Definition calculate If calculate is chosen the program will set EZERO to the

value that it calculates for the energy of the reactants.

read # The read # option, where # is the value of the energy of the

reactants in units specified by the EZUNIT keyword, causes the

program to set EZERO to #.

Example: EZERO read 0.1354

Notes:

(1) If the read # option is chosen, the user must ensure that # is the value of the

energy of the reactants in units specified by the EZUNIT keyword.

(2) If the WKB method is used for any of the vibrational modes of reactant 1, then the

read # option must be used. Otherwise the user can choose calculate.

(3) Another possible use of read # would be to allow efficient calculations for

cases where the reactant energy is already known and would be expensive to recalculate.

However Polyrate always calls at least one of the hook routines for the reactants, so this

efficiency must be implemented by the user if desired.

EZUNIT

EZUNIT is a variable keyword specifying the units used for the zero of energy. The

default is a.u. The other valid option is kcal. Note 1 a.u. = 627.5095 kcal/mol. This

keyword must be read before reading the value of the zero of energy with the read #

option for the keyword EZERO, if that option is used.

Option Definition a.u. atomic units (hartrees)

kcal kcal/mol

Example:

EZUNIT kcal

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EZERO read 100.1354

POTENTIAL

POTENTIAL is a variable keyword that allows the user to specify the source of the potential

energy information for a single-level calculation or for the lower level of a dual-level calculation. In the current version of Polyrate there are five valid options: hooks,

unit29, unit30, unit31, or unit40. The option hooks means that the user is

providing potential information through the hooks. When Polyrate is used as a stand-

alone package, the hooks call SURF and SETUP; this is how one supplies an analytic

potential energy surface (as discussed in Section 8 of this manual). If unit29 is used

the information is read from file fu29 for an IVTST-0 or IVTST-1 calculation. Specification of one of the keywords unit30, unit31, or unit40 means that the

MEP data is to be read from file fu30, fu31, or fu40, respectively. (as discussed in

Sections 9 and 12.C, 12.D, and 12.E of this manual) The fu30 and fu40 options

(unit30 and unit40, respectively) are called the electronic structure input file options

in older versions of POLYRATE.

The default is hooks. Derivative versions of Polyrate will also have various options for

interfacing with electronic structure packages like ACES II, GAUSSIAN, MOPAC, AMSOL,

etc. This may occur through the hooks (modular mode) or in a less general fashion (non-

modular mode), but now electronic structure input can be used with any of the five

choices of POTENTIAL.

Option Definition hooks use the hooks

unit29 read in from electronic structure file fu29

unit30 read in from electronic structure file fu30

unit31 read in from electronic structure file fu31

unit40 read in from electronic structure file fu40

Example: POTENTIAL unit30

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12.A.4. SECOND section

The SECOND section is used to define the method for computing the Hessian of the

reacting system when the POTENTIAL keyword is set to the hooks option; this section

should not be included if the option selected for POTENTIAL is unit30, unit31, or

unit40. The table below lists all the valid keywords for the SECOND section. In the

alphabetical glossary that follows a more complete explanation for each keyword is

given.

Basic:

Keyword Type Default Description

HESSCAL variable ghook how to calculate Hessians

Second derivative Polyrate methods:

Keyword Type Default Description

Other:

FPRINT switch off print second derivative information

NUMSTEP variable 1 10-4 au step size for 2nd derivatives of V

NUMTYPE variable Central method for computing 2nd deriv.

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Glossary of SECOND keywords

FPRINT (NOFPRINT)

FPRINT is a switch keyword that is used if the normal mode energies, eigenvectors and

eigenvalues are to be printed following the normal mode analysis in fu6 output file.

Default is NOFPRINT.

HESSCAL

HESSCAL is a variable keyword specifying how to calculate Hessians. The default is

ghook which means Polyrate will calculate the Hessians by finite differences from the

gradients as specified by NUMTYP. Another option is hhook which means the Hessians

are evaluated by calls to the HHOOK subprogram. See Section 8.C.

Option Definition

ghook call GHOOK to get first derivatives, and use central

differences to compute the second derivatives of the

potential. The step size used is given by the NUMSTEP

keyword.

hhook call HHOOK to get second derivatives.

Example: HESSCAL ghook

NUMSTEP

NUMSTEP is a variable keyword giving the step size in unscaled angstrom (default) or in

unscaled bohr (by specifying the keyword INPUNIT AU) for the numerical second

derivative of potential energy function with respect to the unscaled atomic coordinates for

frequency calculations. The default value is 1.0 10-4 bohr.

Example: NUMSTEP 0.00005

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NUMTYP

NUMTYP is a variable keyword that is used to specify the method for computing the

numerical second derivatives of the potential energy with respect to unscaled atomic

Cartesians if HESSCAL is ghook. See Section 10.C. The default is central. The

allowed options are:

Option Definition central use central differences of analytic first derivatives to compute

the second derivatives of the potential. The step size used is

given by the NUMSTEP keyword.

quadratic use a quadratic fit of the potential to compute the second

derivatives of the potential. The step size used is given by

the NUMSTEP keyword.

fourth use a fourth order polynomial fit to the analytic first

derivatives to compute the second derivatives of the

potential. Step sizes used are NUMSTEP and 2*NUMSTEP.

Example: NUMTYP fourth

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12.A.5. OPTIMIZATION section

The OPTIMIZATION section is used to specify the method for carrying out geometry

optimizations when the POTENTIAL keyword selection is hooks. This section is not

needed if POTENTIAL is set to unit30, unit31, or unit40. The table below lists all

the valid keywords for the OPTIMIZATION section. In the alphabetical glossary that

follows, a more complete explanation for each keyword is given.

Basic:

Keyword Type Default Description

OPTMIN variable bfgs how to optimize minima

OPTTS variable nr how to optimize transition state

Two optimization routines are available in POLYRATE. The first is quasi-Newton with

BFGS Hessian updates. The alternative is Newton-Raphson with Brent line

minimization, which is called the NR method. For minima (equilibrium structures of

reactants and products), the default optimizer is BFGS. For saddle points (transition

states), the default optimizer is the NR method. See Section 6.E for further details.

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Polyrate optimization methods:

Keyword Type Default Description

Common:

PRINT switch off print geometrical parameters and

derivatives after each opt step

Other:

DLX2 variable 1 x 10-5 au step size for first derivative of

grad in geometry optimization

EFOPT list off indicate the option for EF

GCOMP variable 1 x 10-5 maximum allowed component of

the gradient for convergence at

the minima

TSGCOMP variable 1 x 10-5 maximum allowed component of

the gradient for convergence at

the saddle point

HREC variable 10 recalculate Hessian every HREC

step for convergence at minima

TSHREC variable 5 recalculate Hessian every TSHREC

step for convergence at saddle

point

NITER variable 50 max number of iterations for opt

RETRY switch off switch to full Newton method if

BFGS optimization fails

SCALE variable 0.2 step size scaling factor in Newton

search

SDSTART switch on(minima

opt)

off(TS opt)

the first optimization step is

steepest-descent

STPTOL variable 1 x 10-5 au “optimization failure” parameter

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Glossary of OPTIMIZATION keywords

DLX2

DLX2 is a variable keyword used to specify the step size in unscaled angstrom (default) or

in unscaled bohr (by specifying the keyword INPUNIT AU) for calculating the first

derivatives of the gradients of the potential energy function in geometry optimization.

The default value is 1 10-5 ao.

Example: DLX2 0.000012

EFOPT

EFOPT is a list keyword used to specify information for the Eigenvector Following (EF)

algorithm. There are five possible variables that may be specified, namely, RMAX, RMIN,

OMIN, DDMAX, and DDMAXTS. The RMAX and RMIN variables bracket the ratio of the

calculated energy to the predicted energy; the defaults are RMIN = 0 and RMAX = 4. The

OMIN variable is used to indicate the minimum of the overlap in the direction which is

determined by the dot product between the eigenvector and the previous followed

direction; the default is 0.0 for reactants and products and 0.8 for a saddle point. The

DDMAX and DDMAXTS variables are used to set the maximum of the trust radius (in

angstroms); the DDMAX variable is used for the reactants and products, and the DDMAXTS

variable is used for the saddle point. The defaults are DDMAX = 0.5 and DDMAXTS = 0.3.

Example: EFOPT

RMAX 2.0

RMIN 1.2

OMIN 0.2

END

GCOMP

TSGCOMP

GCOMP and TSGCOMP are variable keywords used to specify the convergence criteria for

optimization of minima and transition states, respectively. The optimization is

considered converged if the maximum component of the gradient in atomic units is

smaller than the value specified. The default value is 1 10-5 Eh/ao for both these

keywords. Sometimes, if the saddle point region is very flat, 1 10-5 is not accurate

enough to produce a good reaction path; in such cases we recommend 1 10-7.

Example: GCOMP 0.000001

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HREC

TSHREC

HREC and TSHREC are variable keywords used to specify how often an accurate Hessian is

to be computed in a BFGS or Newton-Raphson calculation. See Section 6.E for more

details. Notice that if the number specified is equal to 1 in a Newton-Raphson calculation

(nr option for keywords OPTMIN or OPTTS), a full Newton method is used. At a step

when the Hessian is not recalculated accurately, the Hessian is either estimated using the BFGS formula (bfgs option for keywords OPTMIN and OPTTS) or kept frozen (nr option

for keywords OPTMIN and OPTTS). The defaults are HREC equal to 10 and TSHREC equal to

5.

Example: HREC 1

NITER

NITER is a variable keyword used to specify the maximum number of iterations to be used

in optimizing the geometry. The default value is 50.

Example: NITER 75

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OPTMIN

OPTMIN is a variable keyword that determines how geometries of minima are optimized.

The default is bfgs.

Option Definition

bfgs specifies to use the Broyden-Fletcher-Goldfarb-Shanno Hessian

update method. The Hessian is calculated using the option

specified in HESSCAL in section SECOND at the initial geometry of

the search; at subsequent geometries, the Hessian is estimated

using information about the Hessian at the previously geometry

and the gradient at the previous and current geometry. (When

the search is complete, the Hessian is again calculated by the

method specified in HESSCAL, and this Hessian is used for

frequencies.)

ef specifies to use the Eigenvector Following algorithm.

nr specifies to use the Newton-Raphson algorithm with Brent line

minimization. ohook optimizes the geometry by calling hooks subprogram OHOOK

using options specified in files fu71 through fu74. See Section

8.C.

Example: OPTMIN bfgs

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OPTTS

OPTTS is a variable keyword that determines how the geometry of the transition state is

optimized. The default is nr.

Option Definition

bfgs specifies to use the Broyden-Fletcher-Goldfarb-Shanno Hessian

update method. The Hessian is calculated using the option

specified in HESSCAL in section SECOND at the initial geometry of

the search; at subsequent geometries, the Hessian is estimated

using information about the Hessian at the previous geometry

and the gradient at the previous and current geometry. (When

the search is complete, the Hessian is again calculated by the

method specified in HESSCAL, and this Hessian is used for

frequencies.)

ef specifies to use the Eigenvector Following algorithm.

nr specifies to use the Newton-Raphson algorithm with Brent line

minimization.. ohook optimizes TS geometry by calling hook subprogram OHOOK

using options specified in file fu75. See Section 8.C.

Example: OPTTS nr

PRINT (NOPRINT)

PRINT is a switch keyword for printing the geometry and the derivatives after each step in

the geometry optimization in fu6 output file. Default is off, i.e., NOPRINT.

RETRY (NORETRY)

RETRY is a switch keyword specifying to switch to full Newton search (HREC = 1, no

linear search) if the optimization stalls (see STPTOL keyword), instead of quitting. Since

this could be quite time consuming, this option has to be used with care. The default is

NORETRY.

Note: the difference between full Newton and quasi-Newton is that full Newton

calculates a full new Hessian at every step whereas quasi-Newton uses an approximate

updated Hessian. In many cases, if the standard search fails it is better to restart the

optimization with a different geometry than to use full Newton.

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SCALE

SCALE is a variable keyword giving the unitless step size scaling factor in the Newton

search for a stationary point. The default value is 0.2.

Example: SCALE 1.1

SDSTART (NOSDSTART )

SDSTART is a switch keyword that specifies to start the optimization with a steepest-descent

step. This is equivalent to defining the Hessian at the starting point as a unit matrix. This

keyword is meaningful only in minima optimizations where BFGS is specified. This option

proves useful in speeding up convergence of the optimization when the starting point

happens to be outside the quadratic region of the surface around the minimum (the initial

guess geometry is bad). The default is SDSTART.

STPTOL

STPTOL is a variable keyword that specify the conditions for optimization failure. The

default unit is angstrom and can also be bohr by specifying the keyword INPUNIT AU. If

the maximum component of the Newton optimization step is smaller than the value

specified by STPTOL, the optimization is considered stalled since the geometry is not

changing anymore, and the program quits. This could happen if the (estimated) Hessian

used is bad; that in turn probably means that either HREC or SCALE are too large. The

default value is 1 10-5 ao.

Example: STPTOL 0.0001

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12.A.6. REACT1, REACT2, PROD1, PROD2, WELLR, WELLP, AND START

sections

The REACT1, REACT2, PROD1, PROD2, WELLR, WELLP and START sections all have the

same set of keywords. A separate section is needed for each reactant and product in the

system and for the saddle point or nonstationary starting point. Thus for a system with

one reactant, one product, and a saddle point the user needs to include the REACT1,

PROD1, and START sections in the input file. For simplicity the keywords have been

broken into two categories: basic and anharmonicity. This is only for clarity in the

manual. The keywords in these categories can be used in any order, except for the

STATUS keyword which must be given as the first option line of a section. Also for

simplicity the keywords in each category have been labeled as either required, common,

or other. The required keyword (GEOM) must be included. The keywords labeled

common are those that might be expected to be found reasonably frequently in input files

for typical Polyrate runs. This labeling is only intended as an aid to the novice user.

Again an alphabetical glossary of all the keywords follows the two summary tables.

Notes that START refers to the saddle point if there is one and to the starting point if there

is no saddle point. Also note that the anharmonicity keywords in the START section

control the anharmonicity all along the reaction path since it must be consistent with the

START point.

The first restart option (See Section 7.C) does not use any of these sections, instead it is

controlled by the RESTART keyword in the GENERAL section. However, the second restart

option (See Section 7.C) is controlled by the STATUS keyword of this section. See the

glossary for the definition and proper usage of the STATUS keyword.

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Basic:

Keyword Type Default Description

Required:

GEOM list required Cartesian coordinates of atoms

Common:

CONSTANT list not used coordinates held constant in opt.

ELEC list

all degen.

= 1

electronic degeneracies

ENERGY variable none energy of the stationary points

EIGENVECTOR list none eigenvector of the saddle point

FREQ switch on perform normal-mode analysis

FREQUNIT variable waven units of the frequencies

HESSIAN list none Hessian of the saddle point

INITGEO variable geom location of input data that specifies initial geometries

STATUS variable 0 status of the stationary point work

SPECIES variable nonlinrp species type (linearity and phase)

VIB list none frequencies of the stationary points

Other:

DIATOM list do not use

Morse

function

treat diatomic as a Morse function

RE variable none Morse equilibrium bond length

BETA variable none Morse range parameter

DE variable none Morse dissociation energy

LINAXIS variable z-axis orientation of a linear molecule

PROJECT switch on project out overall trans. and rot.

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Anharmonicity:

Keyword Type Default Description

Common:

ANTLR variable 1 10-8 criterion on Morse xe

DEMIN variable 0.159 lowest dissociation energy (D)

DQQP variable 0.0001 au,

0.001 au

two distances for quad.- quar. fit

HARMONIC switch on all modes harmonic

MORSE switch off all modes Morse

MORSEQQ switch off all modes Morse/quadratic–quartic

MORMODEL variable morsei Morse options

PRMODE switch off print XMOL movie clips

QQWKB switch off WKB with a quadratic-quartic fit

QQSEMI switch off semi-classical WKB with a quadratic-quartic fit to potential

TOR list not used information for modes treated as torsions

TOROPT list not used more information for modes treated as torsions

VANHAR list not used each mode is treated individually

VRANGE list not used each mode is treated individually for a given range of s

WKB list not used WKB with true potential

WKBTOL variable 1 10-8 tolerance for finding eigenvalues

KBQUAD variable 40 no. of quad. points in phase integrals

KBPRINT switch off print turning points

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Glossary of REACT1, REACT2, PROD1, PROD2, WELLR, WELLP, and START keywords

ANTLR

ANTLR is a variable keyword whose argument is the criterion on the unitless Morse

anharmonicity parameter, xe, such that the quadratic-quartic model is used if xe < ANTLR.

The antlr keyword is only used with the morseqq method. The default value is 1

10-8.

Example: ANTLR 0.000013

CONSTANT

CONSTANT is a list keyword used to specify which of the Cartesian coordinates should be

held constant during the Newton search to find the species' equilibrium geometry. In this

list the unique atom number is used along with x, y, and/or z for those coordinates to be

held constant. The default is that all coordinates are optimized. In most cases the user

needs to specify at least six Cartesians coordinates to be constant for a nonlinear species

and five for a linear species. Note that if this keyword is specified, the default is erased,

and the user should input all the coordinates which are to be held constant.

Example: CONSTANT

1 X Y Z

2 Y Z

3 Z

END

DEMIN

DEMIN is a variable keyword used to input the lowest reactant or product dissociation

energy in a.u., measured from the reactant limit. This is called D in published papers. It

is needed for any of the Morse anharmonicity options and for VT calculations. There is

a default value of 0.159 Eh (= 100 kcal/mol) for this variable but it is dangerous to use

the default. The user is strongly encouraged to understand D if Morse anharmonicity is

used.

Example: DEMIN 0.1733

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DIATOM

DIATOM is a list keyword that is used if the particular reactant or product is a diatomic

molecule and is to be treated as a Morse oscillator. The default is to treat diatomics by

the same methods as any other kind of molecule; thus this keyword would not be used.

Note that if the DIATOM option is chosen, then the user must specify all three options, Re,

and De, which are the Morse parameters for equilibrium geometry, dissociation

energy, and range parameter, respectively. and De are in atomic units and Re is in

angstrom by default and also can be in bohr by specifying the keyword INPUNIT AU. There are no defaults for these options. The example below corresponds to the O2

molecule.

Example: DIATOM

RE 2.3158

BETA 1.4694

DE 0.1779

END

DQQP

DQQP is a variable keyword with two arguments, which are respectively the first and

second step sizes used when fitting the quadratic-quartic potential to two points along the

normal coordinate. It is in angstrom by default and also can be in bohr by specifying the

keyword INPUNIT AU. Note that the first argument (the first step size) must be less than

the second. DQQP is to be used only if one of the keywords QQWKB or QQSEMI is

specified. Default is 1 10-4 ao and 1 10-3 ao.

Example: DQQP 0.03 1.2

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EIGENVECTOR

This keyword should be used only in a START section and it should be used if and only if

the STATUS option is equal to 6. EIGENVECTOR is a list keyword that is used to specify the

eigenvectors of the saddle point in an unscaled Cartesian coordinate system. The

eigenvectors of the stationary point should be given in full matrix form with the columns

being a particular mode. In addition, the axes must be consistent with the geometry in

GEOM.

Example: EIGENVECTOR

L11 L21 L31 L41 L51 L61

L12 L22 L32 L42 L52 L62

L13 L23 L33 L43 L53 L63

L14 L24 L34 L44 L54 L64

L15 L25 L35 L45 L55 L65

L16 L26 L36 L46 L56 L66

END

Explanation of example:

Lij is the jth component of the ith eigenvector. Note that j = 1 is for the x

component of atom 1, j = 2 is for the y component of atom 1, j = 3 is for the z

component of atom 1, j = 4 is for the x component of atom 2, etc. Note also that

the eigenvalues must be in reverse canonical order (this order is described in Sect.

6.E). Thus, I=1 is for the imaginary-frequency normal mode, then come the

eigenvectors corresponding to translations and rotations, and finally come the true

vibrations, in order of increasing frequency.

ELEC

ELEC is a list keyword used to specify the degeneracy and energy in atomic units of each

electronic state of this species. Up to three states are allowed. The ground state should

be given first. The default is for all three states to be singly degenerate. The example

given below is for the 3P multiplet of an oxygen atom.

Example: ELEC

5 0.00000000

3 0.00072218

1 0.00103201

END

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ENERGY

This keyword should be used if and only if STATUS 4. ENERGY is a variable keyword

that is used to specify the energies (a.u.) of a reactant, product, or saddle point.

Example: ENERGY -2.4221970828E-02

FREQ (NOFREQ)

The FREQ keyword is used to specify whether normal mode analysis is carried out. The

default is FREQ.

FREQUNIT

The FREQUNIT keyword is used to specify the units of the frequencies read by the FREQ

keyword. The default is au.

Option Definition

waven Frequencies are given in cm−1.

au Frequencies are given in atomic units.

GEOM

GEOM is a list keyword that is required for all calculations except those with the readfu1

or readfu1&2 option selected for RESTART in the GENERAL section. In this list the

Cartesian coordinates of all atoms in this particular reactant, product or reaction path

species must be given along with each unique atom number. If STATUS (see below) is 0,

the user should choose a geometry that is a guess to the species' stationary-point

geometry. IF status is 2, then the geometry should be the correct geometry, not just a

guess. (See the ATOMS keyword in the GENERAL section for the definition of the unique

atom number. This number must be consistent for each atom in ATOMS and GEOM.) For a

linear species, the user must specify a linear geometry. The example below is for the

same deuterated water molecule used in the ATOMS example. It is in angstrom by default

and also can be in bohr by specifying the keyword INPUNIT AU (not mass-scaled).

Example: GEOM

1 0.000000 0.000000 0.000000

2 -0.241497 -0.945827 0.000000

3 0.956805 0.000000 0.000000

END

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HESSIAN

If the option of the STATUS keyword is 4, the Hessian of the saddle point should be read

in as a triangular form in unscaled Cartesians. HESSIAN is a list keyword that is used to

indicate the Hessian (hartrees per square bohr) of the saddle point. This keyword is only

valid for the START section, and can not be used in the REACT1, REACT2, PROD1, and

PROD2 sections. In addition, the axes must be consistent with the geometry given in

GEOM. The format is free format, with any number of entries per line and entries on the

same line separated by one or more spaces. Since the Hessian should be a symmetric

matrix we read only the lower triangular part.

Example: HESSIAN

F11 F21 F22 F31 F32 F33

F41 F42 F43 F44 F51 F52

F53 F54 F55 F61 F62 F63

F64 F65 F66

END

Explanation of the example:

The element Fjj’ of the Hessian matrix F corresponds to the same order of

components as explained for j under the EIGENVECTOR keyword.

HARMONIC

HARMONIC is a switch keyword that is used when one wishes to treat all vibrational

modes harmonically. It is the default; i.e., if no keyword is given for anharmonicity then

the harmonic approximation is used. The default is that harmonic is on, so when it is

specified, the purpose is just for clarity (i.e., to make the default explicit).

INITGEO

INITGEO is a variable keyword that is used to indicate the location of the input data that

specifies the initial reactant 1, reactant 2, product 1, product 2, and starting geometries.

The default is geom. The valid options are:

Option Definition geom the initial geometries are taken from the lists following the GEOM

keywords in the react1, react2, prod1, prod2, and start sections of

the fu5 input file.

hooks the initial geometries are taken from the external input files fu71-

fu78.

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Example: INITGEO geom

LINAXIS

LINAXIS is a variable keyword that is used to indicate the orientation of a linear reactant,

product, or starting molecule. The default is that LINAXIS is off if the initial geometry is

nonlinear and that it is on if the initial geometry is linear. If LINAXIS is on, but no option is specified, the default value is z-axis. The valid options are:

Option Definition

x-axis the linear molecule is aligned with the x-axis

y-axis the linear molecule is aligned with the y-axis

z-axis the linear molecule is aligned with the z-axis

MORMODEL

MORMODEL is a variable keyword that is used to specify which Morse model is to be

used. This keyword is used only if the MORSE or MORSEQQ switch is on. The default is

morsei. Note that the value of DEMIN is specified by the user using the keyword

DEMIN. All the valid options are given below (see Ref. 1 in Sec. 21 for explanations of

these models):

Option Definition

morsei Morse I: VMEP + local D = DEMIN

morseii Morse II: local D from V'''

morseiii Morse III: Morse II if (VMEP + local D) > DEMIN; otherwise

Morse I

morseia Morse Ia: like Morse I except use hyperradius to determine

side of MEP on which concave-side turning point is to be

found if SCT or LCT tunneling correction is done. morseiiia Morse IIIa: like Morse III except replace Morse I by Morse

Ia, i.e., find direction of concave side from hyperradius when

using Morse I and find it using 3rd derivative when using

Morse II

Example: MORMODEL morseiii

MORSE

MORSE is a switch keyword that is used if all vibrational modes are to be treated using the

Morse approximation with the same value of MORMODEL. If this option is chosen, then

the Morse model is specified by the keyword MORMODEL. Default is off.

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MORSEQQ

MORSEQQ is a switch keyword that is used if all vibrational modes are to be treated using

Morse/quadratic-quartic approximation with the same value of MORMODEL. This means

that the Morse model is used for modes with Morse anharmonicity parameter xe ANTLR,

and the quadratic-quartic option based on second and fourth derivatives of the potential

along the generalized normal mode is used for modes with xe < ANTLR. If this option is

chosen, then the Morse model is specified by the keyword MORMODEL. Default is off.

PRMODE

PRMODE is a switch keyword used to print movie clips of the vibrational modes for the

XMOL program in XYZ format. The file name of a movie clip consists of two parts. The

first part has 4 letters which is used to indicate the type of the species: R1MD for reactant

1, R2MD for reactant 2, P1MD for product 1, P2MD for product 2, RWMD for reactant

well, PWMD for product well, or TSMD for the saddle point. And the second part has a

three-digit integer which is used to indicate the index of the vibrational mode in

decreasing order. Therefore, the maximum number of vibration modes for which this

keyword can be used is 999. Currently, each clip has 20 frames.

PROJECT (NOPROJECT)

PROJECT is a switch keyword that tells the program to use projection operators to remove

overall translations and rotations from the second derivatives at the stationary points.

This projection is not optional along the reaction path, but is optional at stationary points.

Even at stationary points, one obtains more stable numerical results if projection is

applied. The default is PROJECT.

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QQSEMI

QQSEMI is a switch keyword that is used if all vibrational modes are to be treated by using

a quadratic-quartic fit to the potential at two distances (specified by the DQQP keyword)

along the generalized normal mode with the uniform semiclassical WKB method for

computing energy levels. See Section 10.B.1. Default is off.

QQWKB

QQWKB is a switch keyword that is used if all vibrational modes are to be treated using

the WKB method with a quadratic-quartic fit to the potential. The fit is done at two

distances, specified by the DQQP keyword, along the generalized normal mode with the

primitive WKB method for computing energy levels. See Section 10.B.1. Default is off. SPECIES SPECIES is a variable keyword that is used to specify the linearity and phase of the reactant, product, or starting species. See Section 6.B for discussion. The default is nonlinrp. The valid options are given below.

Option Definition

atomic species is a single atom

linrp species is a linear reactant or product

nonlinrp species is a nonlinear reactant or product

ssrp species is a solid-state reactant or product

lints species is a linear transition state or generalized transition state

nonlints species is a nonlinear transition state or generalized transition state

ssts species is a solid-state transition state or generalized transition

state

Example: SPECIES linrp

STATUS

STATUS is a variable keyword that is used to indicate the status of the stationary points.

When the STATUS keyword is used it must be given as the first option line of the

*REACT1, *REACT2, *PROD1, *PROD2, *WELLR, *WELLP, or *START section in which the

keyword is used. The options are:

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option *REACT1, *REACT2, *PROD1, *PROD2,

*WELLR, or *WELLP *START

0 calculate geometry, energy, and

frequencies

calculate geometry, energy,

frequencies, and eigenvectors

2 read in geometry;

calculate energy and frequencies

read in geometry;

calculate energy, frequencies, and

eigenvectors

4 not available read in geometry, energy and Hessian;

calculate frequencies and eigenvectors

6 read in geometry, energy, and

frequencies

read in geometry, energy, frequencies,

and eigenvectors*

* Note: if cubic is chosen as the value of the FIRSTEP keyword in the PATH section, then

option 6 is not valid.

Note that in the START section if STATUS is 4, then the ENERGY and HESSIAN lists must be

given and if STATUS is 6, then the ENERGY, FREQ, and EIGENVECTOR lists must be given.

The GEOM keyword is always required.

Example: STATUS 2

TOR

TOR is a list keyword that is used to specify the information needed for torsional modes

that will be treated using the hindered-internal-rotator approximation. Note that the MS-

T method is not included in this keyword list, but MS-T can be specified in the PATH

section using the SSTOR keyword. The hindered internal rotator approximation is only

used for a subset of the modes, and this keyword is used to give the parameters for each

of those modes. The user must also use the VANHAR or VRANGE (for generalized

transition states) keyword to specify which mode or modes are to be treated as hindered

internal rotation. There should be one line in the TOR list for every mode treated as a

hindered rotor. There are no defaults. If VANHAR or VRANGE specifies that a mode is to

be treated as a hindered rotor, the line for that mode must be present in the TOR list.

The SRPG is the recommended method when using the TOR keyword. Other methods may

be appropriate for certain systems, but careful analysis should accompany any other

choice. See Ref. 52 and 62 of Sect. 21 for a study and comparison of torsion methods.

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The input required for each hindered rotator mode is:

MODE P M METHOD N

where

MODE = mode number m

P = number P of distinct minima along the torsional coordinate

M = number M of total minima along the torsional coordinate (M P)

METHOD = one of six methods defined in Section 10.3:

CT Chuang-Truhlar interpolatory method

RPG Torsional Pitzer-Gwinn method

SRPG Segmented Torsional Pitzer-Gwinn method

AS Ayala-Schlegel method

SAS Segmented Ayala-Schlegel method

FR Free Rotor

N = number N of atoms in first subgroup

The user needs to be cautious with the definition of number of distinct minima along the

torsional coordinate. For example, H2O2 has two minima that have the same energy and

frequencies, but they are mirror images of one another, and one cannot be superimposed

to the other. Therefore they are distinguishable. The total symmetry number is the ratio of

M/P, which should not be a non-integer number. Here are a few examples for the values

of P and M.

Molecule P M

CH3-CH3 1 3

ClCH2-CH3 1 3

HO-OH 2 2

ClCH2-CH2Cl 3 3

ClCH2-CH2 3 6

Among the six methods for torsional treatment, SRPG is recommended. Note each

method requires a different set of keywords. For more input information see the

TOROPT section below.

Example: TOR

10 1 3 SRPG 4

END

TOROPT

TOROPT is a list keyword that must be given for modes treated as hindered rotors . Each

record of TOROPT is a single line of the form:

MODE DATATYPE list of values

An END line signifies the end of all records in the list.

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Which quantities may appear in the list of values depends on DATATYPE. The allowed

values for DATATYPE and the associated lists are as follows:

DATATYPE list

ISB 1i , 2i , …, Ni (the indices of the atoms in the first

subgroup)

NBOND indices of the two atoms that define the rotation axis

(used only when the curvilinear option is used to

calculate the moment(s) of inertia)

CTSCHEME OW/RO/CO/RW/CW/RWO/CWO (one of seven

schemes defined in Ref. 52 of Sect. 21 for CT

method)

CTLEVEL FULL/SF/SC (one of three levels for CT

method)

OMEGA 2w , …, Pw (the frequencies in cm-1)

U 2U , 3U , …, PU (excitation energies in cm-1)

I 2I , 3I , …, PI (moments of inertia in mea02)

READI

 

I1 (moment of inertia in mea02)

W 1W , 2W , …, PW (barrier heights in cm-1)

WL

 

WL1,

 

WL2, …,

 

WLP (

 

WL j is the barrier

height from

the minimum j to the maximum on its left in cm-1)

WR

 

WR1,

 

WR2, …,

 

WRP (

 

WR j is the barrier

height from

the minimum j to the maximum on its right in cm-1)

RATIOL RL1, RL2, …, RLp (RLj is the torsional angle

difference between the minimum j and the maximum

on its left in degrees)

RATIOR RR1, RR2, …, RRp (RRj is the torsional

angle

difference between the minimum j and the maximum

on its right in degree)

The methods specified in the TOR section need different DATATYPE values and the

associated lists. Note that ISB and NBOND are always required except when

CTSCHEME = OW or READI is used. An explanation of DATATYPE requirement for

each method is given below

1. The RPG and AS methods require the following DATATYPE values:

ISB, NBOND, I, WL, and WR

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In these methods the moment of inertia of the torsional motion I1 is calculated by

the curvilinear model using the input geometry in fu5 file, and the others are given

by the user. The user can run jobs to obtain I2, …, Ip using the corresponding

geometries. The barrier height used in the RPG and AS methods is taken as the

average of the input WL and WR values. The frequency of the lowest minimum is

used.

2. The SRPG and SAS methods require the following DATATYPE values:

ISB, NBOND, I, U, WL, WR, RATIOL, and RATIOR

The SPRG and SAS methods need the same information as their corresponding

non-segmented counterparts except that U, RATIOL and RATIOR are also

required.

3. The FR method require the following DATATYPE values:

ISB, NBOND, and I

4. The CT method requires the following DATATYEP values:

ISB, NBOND, CTSCHEME, CTLEVEL, OMEGA, U, and I.

CTSCHEME list is one of the seven schemes defined in Ref. 52 of Sect. 21:

OW Scheme W

RO Scheme R

CO Scheme C

RW Scheme RW

CW Scheme CW

RWO Calculate I with the R-scheme, read in W, obtain from normal mode or

generalized normal-mode analysis

CWO Calculate I with the C-scheme, read in W, obtain from normal mode or

generalized normal-mode analysis (default)

CTLEVEL list is one of the three approximation levels used for CT method defined

in Ref. 52 of Sect. 21:

FULL full (default)

SF single-frequency

SFE single-frequency and single-energy

Note that the SFE method treats the P minima using the same I, , and W as the input geometry in fu5 file and do count the contributions of the P minima to the

partition function. The single-conformer (SC) method defined in Ref. 52 of Sect. 21

is a special case of SFE method when P equals 1.

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In the seven distinct schemes, R represents using the rectilinear model to calculate

the reduced moments of inertia of the torsional motion (see refs. 24, 29, and 30 in

Sect. 21 for detailed description of the rectilinear model), and C represents using the

curvilinear model to calculate the reduced moments of inertia of the torsional

motion (Ref. 59 in Sect. 22 gives a detailed description of the curvilinear model).

Compared with the rectilinear model, for which one only needs to indicate which

atoms are in each of the two fragments of the hindered rotation, the curvilinear

model requires this information and also a choice of internal rotation axis (by using

the NBOND keyword) and an assignment (by using the ISB keyword) of the lighter

fragment as the rotational top. The first five schemes use the relationship given by

Eq. (12) of Ref. 52 in Sect. 21 to calculated either I, W, or from the other two.

The RWO and CWO schemes require I, W, and , and use these variables in the

equations of Ref. 52 in Sect. 21 without forcing a relationship between them.

If CTSCHEME = CO or C, then the sum of the masses of the atoms in ISB must be

less than or equal to the sum of the masses of the atoms not in ISB. Note that the

values of P and N that appear in these definitions are specified using the TOR

keyword. In the current version of POLYRATE, the values of OMEGA, U, and W are

assumed to be independent of the value of the reaction coordinate s. That is, only

values for the stationary points can be read in, and for the non-stationary points

along the reaction path, the only hindered rotor parameters that can depend on s are

the value of 1, which is obtained directly from generalized normal mode analysis

if the OW, RO, or CO scheme is used, and from the moments of inertia of the

lowest minimum along the torsion mode, which are computed from the geometry if

the CO or CW scheme is used and from the geometry and normal mode eigenvector

if the RO or RW schemes is used.

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The set of data types expected in the TOROPT list for CT method depend on the

choices of CTSCHEME and CTLEVEL and the number of distinguishable

minima P. In particular, the expected records are:

Choices in DATATYPES expected in TOROPT

P CTLEVEL CTSCHEME Other expected DATATYPES

1 any OW W ( 1W only)

1 any RO ISB

1 any CO ISB, NBOND

1 any RW ISB, NBOND, W ( 1W only)

1 any CW ISB, NBOND, W ( 1W only)

>1 FULL OW U, OMEGA, W

>1 FULL RO ISB, OMEGA, U, I,

>1 FULL CO ISB, NBOND, OMEGA, U, I,

>1 FULL RW ISB, U, I, W

>1 FULL CW ISB, NBOND, U, I, W

>1 SF OW U, W

>1 SF RO ISB, U, I

>1 SF CO ISB, NBOND, U, I

>1 SF RW ISB, U, I, W ( 1W only)

>1 SF CW ISB, NBOND, U, I, W ( 1W only)

>1 SC OW W ( 1W only)

>1 SC RO ISB

>1 SC CO ISB, NBOND

>1 SC RW ISB, W ( 1W only)

>1 SC CW ISB, NBOND, W ( 1W only)

If values are not expected but are given anyway, then these values will be ignored.

The program will not check the correspondence of the TOR and TOROPT keyword

options; it is users’ responsibility to check if the calculation is meaningful. The

defaults are jw = frequency obtained from normal mode analysis at point on

reaction path (j = 1, 2, …, P), jW = 1000 cm-1 (j = 1, 2, …, P), jU = 0, ISBN =

{1 2 3 4}, and NBOND = {4 5}.

The READI option is used to read in the moment of inertia for the initial configuration.

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Example for using CT method with OW and FULL options: TOR

17 2 2 CT 4

END

TOROPT

17 CTLEVEL FULL

17 CTSCHEME OW

17 U 1000.

17 ISB 1 2 3 4

17 OMEGA 110.

END

Example for using CT method with CW and SC options:

TOR

18 1 1 CT 3

END

TOROPT

18 CTLEVEL SC

18 CTSCHEME CW

18 ISB 3 4 5

18 NBOND 2 6

18 W 1450.0

END

Example for using SRPG method:

TOR

6 2 2 SRPG 2

END

TOROPT

6 ISB 1 4

6 NBOND 1 2

6 WL 2545.505 376.905

6 WR 376.905 2545.505

6 RATIOL 112.504 67.496

6 RATIOR 67.496 112.504

VANHAR

VANHAR is a list keyword that is used to specify variable anharmonicity, i.e., that each

vibrational mode is to be treated differently. The default are that all modes be treated

harmonically. This keyword is used to specify those modes that are to be treated

anharmonically. The valid choices are harmonic, morse, morseqq, qqwkb,

qqsemi, and tor. (Note that modes for which the harmonic option is wanted need not

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be included in the list since it is the default.) Note that for each of these anharmonicity

options there may be other variables that have to be set, and in each case there is keyword

with the same name as the choices just given, i.e., harmonic, morse, morseqq, qqwkb,

qqsemi, and tor. In specifying the modes, note that they are always numbered in order of

decreasing frequency, regardless of symmetry, and that degenerate modes get two

numbers.

The input required is:

mode anharmonicity method

Example: VANHAR

3 tor

5 qqsemi

END

VIB

If the option of the STATUS keyword is 6, frequencies of the stationary point should be

read. VIB is a list keyword that is used to specify the frequencies (a.u. or cm−1 as

determined by FREQUNIT) of a reactant, product, or saddle point. The number of

frequencies to be read is always F, where F is 3N − 6 for nonlinear stationary points, 3N

− 5 for linear stationary points, and 3N for solid-state stationary points. For reactants and

products there should be F real frequencies, and they should be given in decreasing order

of their magnitude. For saddle points, the F − 1 real frequencies should be given first in

decreasing order followed by the imaginary frequency given last as a negative number.

Example: VIB

1.72881D-02 1.72881D-02 1.62501D-02 8.24925D-03

8.07930D-03 8.07884D-03 7.06232D-03 7.06187D-03

6.58527D-03 3.28102D-03 3.28102D-03 -1.24729D-02

END

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VRANGE

VRANGE is a list keyword similar to VANHAR except that a range of s values can also be

specified for each mode. This means that except for the given modes and their respective

ranges of s, each mode will be treated harmonically. Again the valid anharmonicity

choices are: harmonic, morse, morseqq, qqwk, qqsemi, and tor. Note that for

each of these anharmonicity options there may be other variables that have to be set. For

more information, please see the keyword glossary entry for each method. This keyword

should only be used in the START section. The default unit of s is angstrom and can also

be bohr by specifying the keyword INPUNIT AU.

The input required is:

smin smax mode number anharmonicity

The example below shows the VRANGE input if one wanted to use the Morse I

approximation in the regions 0.01 s 0.5 and –0.15 s -0.01 for mode #2 and the

harmonic approximation everywhere else.

Example: VRANGE

-0.15 -0.01 2 morsei

0.01 0.50 2 morsei

END

WKB

WKB is a list keyword that is used if the zero point eigenvalues are to be computed using

the WKB method with the true potential. See Sections 10.B and 12.B.2. The WKB

keyword applies only to the ground state; another anharmonicity method must be chosen

for the excited states, or else the excited states will be calculated harmonically. The

options in this list control the WKB calculation. They are defined as follows:

Option Description Default

wkbtol tolerance for finding WKB eigenvalues in hartrees 110-8

kbquad number of quadrature points used in calculating WKB 40

phase integrals

kbprint switch for printing values of turning points off

Example: WKB

wkbtol 0.0000002

kbquad 30

kbprint

END

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12.A.7. PATH section

The PATH section contains the keywords that control the calculation of the reaction path

and the properties along the path. This section is not used in a restart calculation. For

simplicity the keywords have been broken into five categories: basic, integrators, step

sizes for the MEP, extrapolation, and print. This is only for clarity in the manual. The

keywords in any of these five categories can be used in any order. Also for simplicity the

keywords in each category have been labeled as either common or other. The keywords

labeled common are those that might be expected to be found reasonably frequently in

input files for typical Polyrate runs. This labeling is only intended as an aid to the novice

user. Again an alphabetical glossary of all the keywords follows the five summary tables.

If only a conventional transition state theory rate constant calculation is desired, one

needs to include this section only if the Hessians are input in mass-scaled coordinates and

SCALEMASS does not equal 1.0 amu.

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Basic:

Keyword Type Default Description

Common:

CARTRP Switch on Whether the normal mode analysis for reactants and products is carried out in Cartesian coordinate

COORD

Variable

cart

type of coordinate system to be used for computing vibrational frequencies and generalized normal modes along the MEP

IDIRECT Variable 1 initial direction off of saddle pt.

INTDEF List not used define curvilinear internal coordinates

NSTEPS Variable 99999 max no. of steps along MEP

SADDLE Switch yes whether the reaction has a saddle point

SCALEMASS Variable 1.0 mass-scaled coordinates scale factor

SIGN Variable reactant direction of unbound eigenvector

SRANGE List not used range of s for MEP

SLP Variable +1.0 au upper limit on s before it is extended by interpolation

SLM Variable –1.0 au lower limit on s before it is extended by interpolation

Others:

CURV Variable dgrad method for computing curvature

DLX3 Variable 1 10-4 au step size for 3rd derivatives of PES

FCSCALE List not used the force constant scaling factors for specified internal coordinate

FREQINCR Variable not used Increase low frequencies to a certain number that is as the value of this keyword

FIRSTSTEP Variable nmode method for first step

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Basic:

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Keyword Type Default Description

Others:

FREQSCALE Variable 1 Scale factor for frequencies

HESS Switch on Compute the Hessian along MEP

INTMU Variable 1 Number of points on each side of the saddle point for interpolation of eff(s)

ISWR Variable Not used mode index of the reactant frequency which is to be scaled

ISWP Variable not used mode index of the product frequency which is to be scaled

IVTSTMOPT List not used IVTST-M options

LBEXP Variable 3 mapping for curvature components

POLYS switch on include 10 extra points for spline fitting

SINCW variable 0.01 au step size for 10 extra points

TENSION variable -1.0 tension for spline under tension

IVTST0FREQ list not used modifies the frequency of a specified mode along the reaction path

NEXTPT switch off only compute next point on MEP

REORDER switch

off order frequencies along MEP by overlaps

SCALERP switch

off scales frequencies in VIB section if turned on

SCLPT switch

off whether scale the potential if FCSCLAE

is used

SPECSTOP List not used special stop for MEP

CURVE Variable vag the curve on which the check for the special stop is made

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POINT Variable savegrid the grid on which the end point for the special stop is chosen

PERCENTDOWN Variable 50. the percentage down from the saddle point for the special stop

SSPECIAL list

no special

s val.

special s values for N.M. analysis

SYMMETRY switch off symmetric reaction path

VSCALE variable 1 scale factor for MEP

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Integrators:

Keyword Type Default Description

Common:

ES1OPT list not used Euler with stabilization

DELTA2 variable 5 10-5 au step size 2 for stabilization

DIFFD variable 1 10-8 magnitude of difference vector

RPM variable ESD reaction path following method

Others:

RODS switch off re-orient the dividing surface

Step sizes for the MEP:

Keyword Type Default Description

Common:

SSTEP variable 5 10-4 au step size for computing MEP

Others:

INH variable 9 ratio of gradients to Hessians

INI variable 1 interval of gradient interpolation step

SFIRST list not used special step size for first n steps

NFSTEP variable 0 number of initial special steps

FSIZE variable 1 10-5 au step size for the special steps

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Reaction coordinate for the VRC:

Keyword Type Default Description

Common:

SVRC list not used Reaction coordinate setting for

reaction path in variable reaction

coordinate algorithm for loose

transition state

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Extrapolation:

Keyword Type Default Description

Others:

EXFIRST list not used extrapolate first direction from saddle point.

EXNSTEP variable 0 number of steps

EXREACT switch off extrapolation is towards reactants

EXPROD switch on extrapolation is towards products

EXSTEP variable 0.03 au step size

EXALPHA variable 1.0 extrapolation range parameter

EXSECOND list not used extrapolate second direction from

saddle point

EXNSTEP variable 0 number of steps

EXREACT switch on extrapolation is towards reactants

EXPROD switch off extrapolation is towards products

EXSTEP variable 0.03 au step size

EXALPHA variable 1.0 extrapolation range parameter

Note: The extrapolation is not performed unless either or both the EXFIRST and EXSECOND

keywords are specified.

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Print:

Keyword Type Default Description

Others:

POTINF variable 0 print n pieces of PES information

PRPATH list not used print reaction-path information to units fu25-fu27

PRINTSTEP switch off print geom. at each save point

PRDISTMX variable 20 print interatomic distance matrices

PRSAVERP variable 9999 print geometry, V, and V ́at each save point

PRSAVEMODE variable 9999 print normal mode information at each save point

SDEBG1

variable

not used

s value for starting debug printing of generalized normal mode vibrational analysis along the MEP

SDEBG2

variable

not used

s value for ending debug printing of generalized normal mode vibrational analysis along the MEP

SPRNT variable 0 extra reaction-path Hamiltonian information printed at large s

SSPECPR switch off print information at special s values

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Nonequilibrium Solvation:

Keyword Type Default Description

BATH list not used nonequilibrium solvation

BATHTEMP variable 298.0 temperature of the solvent in K

CUPLCNST list not used coupling constants in mass-scaled

atomic units (A)

DIFFUSION list not used diffusion coefficients in 10-5 cm2s-1

FRICTION variable 0 solvation time in fs

Torsional Anharmonicity

Keyword Type Default Description

SSTOR list not used MS-T torsional anharmonicity

along the reaction path by carrying

out a single-structure (SS)

calculation as described in Section

10.O.

MTOR variable no default local periodicities of torsions

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Glossary of PATH keywords

BATH

BATH is a list keyword specifying the parameters used for a nonequilibrium solvation

calculation. For detailed description, see Ref. 53 in Sect. 21. There are 4 options:

Keyword Description

BATHTEMP temperature of the solvent in K

CUPLCNST atomic coupling constants of the solvent coordinate to the solute

in mass-scaled atomic units

DIFFUSION effective atomic diffusion constants in 10-5 cm2s-1

FRICTION solvent friction time in fs (Note: the friction time is also called

the solvation time)

Example: BATH

FRICTION 10.0 # in fs

DIFFUSION # in 10-5 cm^2s^-1

1 8.08

2 12.62

3 1.72

4 3.04

5 33.08

6 192.27

7 50.52

END

BATHTEMP 298.0

END

CARTRP (NOCARTRP)

The keyword CARTRP is used to declare explicitly that the reactant and product normal

mode analysis is carried out in Cartesian coordinates. The purpose of adding this

keyword is to allow the use of curvilinear coordinate normal mode analysis. In versions

of Polyrate earlier the 8.6, the normal mode analysis for reactants and products was

always carried out in Cartesian coordinates even though the normal mode analysis for

transition states can be carried out in curvilinear internal coordinates. The default is

CARTRP.

Note: CARTRP should not be used when scaling factors for principal force constants in

curvilinear internal coordinates (FCSCALE) are used.

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COORD

COORD is a variable keyword specifying the type of coordinate system for calculating the

bound-state vibrational frequencies and normal mode eigenvectors along the MEP. It is

very important to use curvilinear coordinates rather than Cartesian coordinates for

generalized normal mode analysis along MEP in VTST calculations; Cartesian coordinate

will very likely yield imaginary frequencies along the reaction coordinate, which will

cause unphysical VTST results. See Sections 6.G.1 and 10.M. The default is cart

(Cartesian coordinates). The valid options are:

Option Definition curv1 use curvilinear internal coordinates for generalized normal

mode analyses using method of Ref. 41 of Sect. 21

curv2 use curvilinear internal coordinates for generalized normal

mode analyses using method of Ref. 43 of Sect. 21

curv3 use redundant internal coordinates for generalized normal

mode analyses using method of Ref. 46 of Sect. 21 cart use rectilinear, i.e., Cartesian coordinates for generalized

normal mode analyses

Note that if the curv1, curv2, or curv3 option is used, the INTDEF keyword

discussed below is required.

Example: COORD curv2

CURV

CURV is a variable keyword used to specify the method for computing the reaction path

curvature components. See Sections 6.H and 10.F for more information about this issue. The default is dgrad. The valid options are:

Option Definition

dgrad use a quadratic fit to obtain the derivative of the gradient with

respect to the reaction coordinate

oneside use one-sided differences for the derivative of the gradient

with respect to the reaction coordinate dhess use Hessian, generalized-normal mode eigenvectors, and

gradient to calculate the reaction path curvature

Example: CURV dgrad

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DLX3

DLX3 is a variable keyword for specifying the step size used for numerical differentiation

in unscaled atomic Cartesians to obtain the 3rd derivatives of V from the Hessian at the

saddle point. These derivatives are required when the cubic starting algorithm is

employed (see FIRSTSTEP). The default unit is angstroms and it can also be in bohr by

specifying the keyword INPUNIT AU. The default is 1 10-4 ao.

Example: DLX3 0.00005

ES1OPT

ES1OPT is a list keyword for using the Euler with stabilization integrator. The user must

give the step size for the finite-difference derivative (DELTA2 keyword) and the tolerance

parameter for the magnitude (in a.u.) of the difference vector between successive

normalized gradients (DIFFD keyword). See Section 10.D. The default unit of step size

DELTA2 is angstroms and it can also be in bohr by specifying the keyword INPUNIT AU.

The defaults are DELTA2 = 5 10-5 ao and DIFFD = 1 10-8.

Example: ES1OPT

DELTA2 0.00001

DIFFD 0.000001

END

EXFIRST

EXFIRST is a list keyword for specifying the extrapolation beyond the limits (SLM and SLP)

of the Hessian grid for the first direction from the saddle point when using the hooks.

(See Section 7.B for a discussion of which direction is first.) The EXFIRST and EXSECOND

keywords cannot be used with units fu30, fu31, or fu40. The extrapolation procedure is

different for reactions with and without a saddle point. The particular extrapolation

procedure to be used is chosen based on the SADDLE(NOSADDLE) keyword in the PATH

section.

For reactions without a saddle point (NOSADDLE specified in the PATH section) the

extrapolation procedure is described in Section 10.A; it is designed to extrapolate VaG(s)

and meff ( )s toward bimolecular reactants or products and should not be used to

extrapolate toward unimolecular reactants or products. If EXFIRST is omitted, no

extrapolation is performed in the first direction, that is, by default no extrapolation is

performed. If no extrapolation is performed, VMEP is set equal to the reactant or product

value beyond the limits, and eff is set to .

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For reactions with a saddle point (SADDLE is specified in the PATH section; or SADDLE is

accepted as the default) the extrapolation procedure is based on the mapped interpolation

algorithm, which is described in Sections 6.N.3 and 10.J and in Ref. 48 of Sect. 21. The

mapped interpolation algorithm is used to extrapolate VMEP, | I |, , and BmF. If EXFIRST

is omitted, no extrapolation is performed in the first direction, that is by default no

extrapolation is performed.

The EXALPHA keyword is only used for reactions without a saddle point.

If the EXFIRST keyword is not specified, then no extrapolation is performed. If the

EXFIRST keyword is specified with an empty list then the extrapolation is performed with

the default values listed below. The keywords in this list and their respective default

values are explained below.

Keyword Description Default

EXREACT extrapolation is towards reactants off

EXPROD extrapolation is towards products on

EXNSTEP number of steps to be taken in extrapolation region 0 EXSTEP mass-scaled step size in the extrapolation region 0.03 ao

for computing the adiabatic potential and other

quantities needed for the tunneling calculations. The

default unit is angstroms and it can also be in bohr by

specifying the keyword INPUNIT AU.

EXALPHA exponential range parameter in reciprocal angstroms (only

used with NOSADDLE). It can also be in reciprocal bohrs by

the keyword INPUNIT AU. 1.0 ao-1

Example: EXFIRST

EXPROD

EXNSTEP 50

EXSTEP 0.1

EXALPHA 0.5

END

Example (empty list, defaults only): EXFIRST

END

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EXSECOND

EXSECOND is a list keyword that is very similar to EXFIRST but is used for specifying the

extrapolation beyond the limits (SLM and SLP) of the Hessian grid for the second direction

from the saddle point when using the hooks. (See Section 7.B for a discussion of which

direction is first.) The EXFIRST and EXSECOND keyword can not be used with units fu30,

fu31, or fu40. See also the discussion of EXFIRST. The EXALPHA keyword is only used

when NOSADDLE is specified in the PATH section. If the EXSECOND keyword is not

specified then no extrapolation is performed. If the EXSECOND keyword is specified with

an empty list then the extrapolation is performed with the default values listed below.

The valid keyword options are defined below.

Option Description Default

EXREACT extrapolation is towards reactants on

EXPROD extrapolation is towards products off

EXNSTEP number of steps to be taken in extrapolation region 0

EXSTEP mass-scaled step size in the extrapolation region 0.03 ao

for computing the adiabatic potential and other quantities

needed for the tunneling calculations The default unit is

angstroms and it can also be in bohr by specifying the keyword

INPUNIT AU.

EXAPLHA exponential range parameter in reciprocal angstroms. It can

also be in reciprocal bohrs by the keyword INPUNIT AU. 1.0 ao-1

Example: EXSECOND

EXREACT

EXNSTEP 50

EXSTEP 0.1

EXALPHA 0.5

END

Example (empty list, defaults only): EXSECOND

END

FCSCALE

FCSCALE is a list keyword used to specify scaling factors for principal force constants of

the selected curvilinear internal coordinates defined in the INTDEF keyword. This

keyword should be used only when internal coordinates defined by COORD curv2 or

COORD curv3 options are used, and the switch keyword FREQ is on. To specify the

selected curvilinear internal coordinates involving force constant scaling, the

connectivities of atoms are required to be defined using the INTDEF keyword as well as

the FCSCALE keyword is used. Each item in the list is in the form of an integer sequence

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number followed by a floating-point scaling factor. The sequence number denotes the

ordinal number of the specific coordinate in the list of all the curvilinear internal

coordinates defined under the INTDEF keyword. (Note: This is not the ordinal number in

internal storage after the code internally re-orders the coordinates.) The corresponding

diagonal element in the force constant matrix will be scaled by the scaling factor. All

scaling factors are set to 1.0000 as the default. In the following example, the sequence

number 8 in FCSCALE represents the stretch between atom 1 and atom 2; thus the diagonal

element in the force constant matrix involving that stretch will be scaled by a scaling

factor of 0.9734.

Example:

INTDEF

1=2=3

2-3-4 2-3-5 2-3-6 4-3-5 4-3-6 5-3-6 1-2 2-3 3-4 3-5 3-6

4-3-5-6

END

FCSCALE

8 0.9734

END

When FCSCALE is used, NOCARTRP should be declared explicitly because the reactant and

product normal mode analysis should be carried out in curvilinear coordinates.

The actual effect of the force constant scaling is controlled by the keyword SCLPT, in

which either the scaling of the potential or the scaling of frequencies is specified. The

default is scaling the frequencies only (NOSCLPT).

Note: Another different way to scale frequencies is with FREQSCALE, in which all

frequencies are scaled by the same scaling factors.

FIRSTSTEP

FIRSTSTEP is a variable keyword specifying the method for taking the first step off the saddle point or starting geometry. The default is nmode. The valid arguments are:

Option Definition

nmode take the first step along the imaginary-frequency normal

mode

cubic use the cubic starting algorithm (see STEP 3)

gradi take the first step along the negative of the gradient direction

[ use this only if NOSADDLE is selected; see Section 6.G ]

Example: FIRSTSTEP cubic

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FREQSCALE

FREQSCALE is a variable keyword for specifying the factor by which to scale the harmonic

vibrational frequencies for partition function calculations. If FREQSCALE is used, the

scaling will be applied to all stationary point frequencies and generalized normal mode

frequencies for generalized transition states along the reaction path. Furthermore, the

vibrationally adiabatic potential energy curve VaG will be calculated by adding the scaled

ZPE to VMEP and all tunneling calculations will be based on this new VaG. The default is

not to scale the frequencies. For kinetics, the scale factor that one should choose is the

one for reproducing the correct ZPE, i.e., the ZPE scale factor, which is available on the

website: https://comp.chem.umn.edu/freqscale/version3b2.htm.

Please notice that, if the vibrational frequencies are directly read in from the .dat

input file, the FREQSCALE will not be applied on these user-input vibrational

frequencies; and therefore, usually, the user-input frequencies in .dat file should have

already been scaled by the user with the same frequency scale factor for the reaction path.

This feature thus also provides the user with an opportunity to use different scale factors

for stationary points and for the saddle point and the non-stationary points on the reaction

path.

Example:

FREQSCALE 0.91

FREQINCR

FREQINCR is a variable keyword for specifying the value to which the frequencies that are

lower than this value to increase (unit is cm-1)

Example:

FREQINCR 200

HESS (NOHESS)

HESS is a switch keyword that determines if the Hessian should be computed along the

MEP. This switch is defaulted to on and in most cases one would want to compute the

Hessian. Most likely this switch will only be used for a special case when the Hessian is

not desired, and thus NOHESS will be used. The default is HESS.

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IDIRECT

IDIRECT is a variable keyword used to specify the direction of the initial step from the

starting point. The allowed arguments for this variable are ±1: +1 if the initial direction

is the direction toward products and -1 if it is towards reactants. See Section 7.B. The

default is 1.

Example: IDIRECT 1

INH

INH is a variable keyword used to specify the ratio of the number of gradients to the

number of Hessians calculated along the MEP. INH must be an integer value. The

default is 9.

Example: INH 4

INI

INI is a variable keyword used to specify the interval of the gradient interpolation steps in

the IVTST-M calculation. INI must be an integer value less than or equal to INH. The

default is 1.

Example: INI 2

INTDEF

INTDEF is a list keyword used to specify the curvilinear internal coordinates used for the

vibrational frequencies and calculations of generalized normal modes. (It is very

important to use curvilinear coordinates rather than Cartesian coordinates for VTST

calculations; Cartesian coordinate will very likely yield imaginary frequencies along the

reaction coordinate, which will cause unphysical VTST results.) The allowed types are

• stretches (i-j),

• bends (i-j-k),

• dihedrals (i-j-k-l), and

• doubly degenerate linear bends (i=j=k)

where i, j, k, and l are the atom-number-labels defined in the GENERAL section.

Note: when the bond angle is close to 180 degrees (i.e., greater than about 175 degrees),

using the doubly degenerate linear bending mode approximation will prevent dividing by

zero or a number close to zero during computations.

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Example: INTDEF

1-2 1-3 3-4 2-1-3 1-3-4 2-1-3-4

END

Note: The pound sign (#) cannot be used as a comment card within the INTDEF keyword

list.

INTMU

INTMU is a variable keyword that indicates the number of points on each side of the

saddle point used for the interpolation of the effective reduced mass at the saddle point.

See Section 6.H. The default value is 1. The valid options are:

Option Definition

1 1 point on either side of the saddle point; thus interpolation is

based on 2 points

3 3 points on either side of the saddle point; thus interpolation is

based on 6 points

Example:

INTMU 1

ISWP

ISWP is a variable keyword for specifying the index of the product frequency that will be

scaled by a factor of (VSCALE)1/2. This keyword is only needed if the VSCALE keyword

is specified and there is only one product species.

Example: ISWP 9

ISWR

ISWR is a variable keyword for specifying the index of the reactant frequency that will be

scaled by a factor of (VSCALE)1/2. This keyword is only needed if the VSCALE keyword

is specified and there is only one reactant species.

Example: ISWR 9

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IVTSTMOPT

IVTSTMOPT is a list keyword for specifying the IVTST-M options for the curvature

components and unimolecular reactions.

The mapping procedure for the curvature components is slightly different from the

mapping for the rest of the parameters. The exponent in equation 19 of Ref. 48 in Sect. 21

has been optimized in order to make the changes of the interpolated curvature

components along the reaction path as close as possible to the changes observed in

converged calculations. Therefore, the user is strongly advised against changing this

parameter without a good reason. If one does have a good reason, though, the exponent

can be set by means of the LBEXP variable option. This keyword can only take positive

odd integer values.

There are two methods for performing IVTST-M calculations for the unimolecular side

(or sides) of reactions with one reactant or/and one product, or wells in one of the

channels: (i) to carry out a spline-under-tension fit (as a function of z) based only on the

input data, or (ii) to carry out a spline-under-tension fit based on ten extra energy points.

The ten extra points are calculated by means of a cubic polynomial fitted to the

unimolecular reactant, unimolecular product, or well, a point calculated from the lowest

real frequency at that minimum, and the two points on the reaction path with the largest

|s| values on the unimolecular side. In the second option generating the extra point from

the frequency requires the choice of a small step-size, whose value is recommended to be

the same as the gradient step-size used in the calculation. The polys option specifies the

treatment to be given to the unimolecular side (or sides), and, the sincw option specifies

the value of the step-size. The default is to use a cubic polynomial for estimating 10 extra

energies, with a step-size along the lowest frequency mode of 0.01 a0 in s, which is mass

scaled.

Option Definition

lbexp value of the exponent for interpolating the curvature components.

The default is 3. polys use a cubic polynomial for estimating 10 energy points before

spline-fitting VMEP(s).

polyz use a cubic polynomial for estimating 10 energy points before

spline-fitting VMEP(z) (default).

nopolys do not include 10 extra points, and base the spline fit on input

data only plus one extra computed as described in Section 10.J.

sincw variable keyword to indicate the step-size along the lowest-

frequency mode to fit the cubic polynomial. The default unit is

mass-scaled angstroms and it can also be in mass-scaled bohr by specifying the keyword INPUNIT AU. The default value is 0.01 a0.

this value is used only if polys or polyz is selected.

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fixmuef keyword used to apply a global interpolation to estimate the

effective reduced mass eff of the SCT algorithm at the saddle

point when the IVTST-M algorithm is used with hooks. The

default option is to use local Lagrangian interpolation for the

effective reduced mass at the saddle point with either one point

or three points (see INTMU keyword option) one each side of the

saddle point. The global interpolation can be used to obtain a

smoother value of eff at the saddle point; it should be used if

and only if the points close to the saddle point suffer from

numerical instability.

tension keyword used to specifically give a tension factor in interpolation

using spline under tension. If this keyword not used, the program

will automatically determine the tension factors. The value for

this keyword must be between 0 an 85. We recommend to use

this keyword only in case very large tension factor is needed.

Example: IVTSTMOPT

lbexp 5

polys

sincw 0.005

END

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IVTST0FREQ

IVTST0FREQ is a list keyword that modifies the frequency of a particular mode along the reaction path. A section for each mode begins with the list option keyword MODE which contains lines with the following keyword options:

Option Definition

index index of the vibrational mode to be interpolated (this is

determined from the frequencies of the saddle point arranged in

decreasing order).

reactant x used to indicate the frequency (in cm-1) at the reactant side (s <

0) for the interpolation with value x. When the reactant is

unimolecular or a reactant well present, the s value has to be

provided with option SR. If a reactant well exists for a

bimolecular reaction, the interpolation uses the frequency at the

well instead of the reactants.

start x used to indicate the frequency at s = 0 for the interpolation.

product x used to indicate the frequency at the product side (s > 0) for the

interpolation with value x. When the product is unimolecular or

a product well present, the s value has to be provided with option

SP. If product well exists for a bimolecular reaction, the

interpolation uses the frequency at the well in stead of the

products. sr x used to indicate the s value at the limit of reactant side (s < 0).

The default unit is angstroms and it can also be in bohr by

specifying the keyword INPUNIT AU. The default value is −1.0

bohr.

sp x used to indicate the s value at the limit of product side (s < 0).

The default unit is angstroms and it can also be in bohr by

specifying the keyword INPUNIT AU. The default value is +1.0

bohr.

The IVTST0FREQ algorithm is similar to the frequency interpolation algorithm of the VTST-IC method. See Section 10.M for a detailed description. Notice that IVTST0FREQ can be used to interpolate a given mode, say i, (where modes are numbered in order of decreasing frequency) from the saddle point to reactants and products. It cannot interpolate between mode i at the saddle point and mode i + 1 at reactants (which might sometimes be useful for unimolecular reactions). It cannot interpolate between mode i at the saddle point and mode i at an intermediate location between the saddle point and reactants. Note that IVTST0FREQ is currently incompatible with using fu31.

Example: For a bimolecular/bimolecular case

IVTST0FREQ

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MODE

index 11 reactant 0

start 300 product 0 END

END For a unimolecular/bimolecular case

IVTST0FREQ

MODE index 11

reactant 50 start 200 product 0

sr -2.0 END END

NEXTPT (NONEXTPT)

NEXTPT is a switch keyword that only works if POTENTIAL = unit30 or unit 40.

When turned on it will cause Polyrate to compute only the next point on the MEP by

taking a single step from the last point in the electronic structure input file, and then stop.

The method used for the step will be ESD (default), or Page-McIver (if PAGEM is

specified). The step size used in this procedure is specified using the SSTEP keyword.

The direction in which one is following the path (towards reactants or products) is

specified using the IDIRECT keyword in conjunction with NEXTPT (IDIRECT = 1 to calculate

the next point to the right; IDIRECT = -1 to calculate the next point to the left). For

example, using the ESD method, turning on NEXTPT causes the following calculation to

be performed

xnext-point = xcurrent – s gcurrent

snext-point = scurrent + (IDIRECT) s

where xcurrent is the mass-scaled geometry corresponding to the last point input on fu30

or fu40, and ˆ g current

is a unit vector in the direction of the mass-scaled gradient at that

point. Thus, to go left, the last point read in should have negative s, and to go right, it

should have positive s.

This option is useful when using Polyrate as a driver to determine geometries for ab

initio calculations. The only print option in unit fu30 compatible with the use of NEXTPT

is LOPT(1) = 0. The default is NONEXTPT.

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NSTEPS

NSTEPS is a variable keyword for specifying the maximum number of steps (after the first

step) along the negative of the gradient of V to be taken in each direction from the saddle

point or starting full-system geometry. The minimum number of steps is the number

required to reach the limits specified by SRANGE. The default is 99999.

Example: NSTEPS 5000

POTINF

POTINF is a variable keyword that specifies how many pieces of data from the potential

energy subroutine are written along the MEP to FORTRAN unit fu6. The default is 0.

See Subsection 8.C.1 for details.

Example:

POTINF 4

PRDISTMX

PRDISTMX is a variable keyword that indicates the interval along the Hessian grid for the

printing of interatomic distance matrices. The i-j element of the interatomic distance

matrix is the distance (in mass-scaled bohr) between atoms i and j. The default is set to

print the interatomic distance matrix at every 20th point along the Hessian grid.

Example: PRDISTMX 20

PRINTSTEP (NOPRINTSTEP)

PRINTSTEP is a switch keyword that specifies that the geometry at each step along the

MEP be printed in fu6 output file. The default is NOPRINTSTEP. See the SPRNT keyword

below.

PRPATH

PRPATH is a list keyword used to set the options for printing reaction-path information to

units fu25-fu27. This keyword is especially useful for analyzing reaction-path data. The

unit fu25 and fu26 output can easily be imported to a spreadsheet, and unit fu27 output is

designed to be read into the XMOL program to visualize the geometry changes along the

reaction path. (The XMOL program is a X-windows-based molecule viewer and format

converter developed by Wasikowski and Klemm at the Minnesota Supercomputing

Center, Inc.) When this keyword is specified, the program will automatically write the

energetic information (VMEP and VaG) to unit fu25. The valid options are defined below.

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Option Description Default coord ai up to 4 atoms, from the full system, can be specified off

for which the bond distances(2, 3, or 4 atoms specified),

the bond angles(3 or 4 atoms specified), and the dihedral

angle(4 atoms specified) are calculated and written to unit

fu28.

interval n write the reaction-path information every n Hessian grid 1

points.

freq mi GTS frequency mode numbers to be printed to unit fu26; not used

a total of up to ten modes can be specified and printed.

xmol write XMOL XYZ input file to unit fu27. off

Example: PRPATH

COORD 1 2 3 6

INTERVAL 5

FREQ 1 2 3

XMOL

END

PRSAVEMODE

PRSAVEMODE is a variable keyword that specifies that (in addition to the items listed for

PRSAVERP) the normal mode eigenvectors, energies, curvatures, and frequencies be

printed at a given multiple of the save point. The default is 9999.

PRSAVERP

PRSAVERP is a variable keyword that specifies that the geometry, potential (V), curvatures,

and gradient (V )́ at a given multiple of the save point along the MEP be printed. The

default is 9999.

REORDER (NOREORDER)

REORDER is a switch keyword that specifies that the frequencies be ordered according to

overlap calculations along the MEP. The default is NOREORDER, which means the

frequencies are in canonical order. See Sections 6.E, 6.F, and 6.G for further discussion.

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RODS (NORODS)

RODS is a switch keyword which specifies that the RODS algorithm is to be used to re-

orient the generalized transition state theory dividing surface. The RODS algorithm can

be used with any of the integrators, ESD, ES1, or PAGEM. See Sect. 10.D. The default

is NORODS, which turns RODS off. When RODS is off, the generalized-transition-state-

theory dividing surface is normal to the gradient.

RPM

RPM is a variable keyword that indicates which integrator is to be used for following the

reaction path. The default is esd. The valid options are defined below.

Option Description esd use the Euler steepest-descents integrator to follow the reaction

path; this is the name we now use for the Euler algorithm, which

is often called the Euler single-step algorithm in textbooks

es1 use the Euler-with-stabilization integrator to follow the reaction

path

pagem use the Page-McIver integrator to follow the reaction path

vrpe use the VRP(ESD) algorithm to follow the reaction path

Example:

RPM pagem

SADDLE (NOSADDLE)

SADDLE is a switch keyword to indicate whether the reaction has a saddle point or not.

See Sect. 6.G. The default value is SADDLE.

SCALEMASS

SCALEMASS is a variable keyword for the reduced mass µ in amu used in defining the

mass-scaled coordinates. This reduced mass is called the scaling mass. See Refs. 1 and 5

of Sect. 21 for an explanation of the scaling mass. Notice that no physical observable

depends on µ, but a single value must be used consistently in the whole calculation. Note

also that certain nonobservable intermediate quantities, most notably the numerical value

of s at any point along the MEP, do depend on µ. The default is 1.0 amu which means

that the mass-scaled coordinates in bohrs have the same numerical values as mass-

weighted coordinates in amu1/2 bohrs. (These are the mass-weighted coordinates made

popular by Wilson, Decius, and Cross in Ref. [36] of Sect. 22.) The variable µ is

discussed in Section 6.A of this manual.

Example: SCALEMASS 0.195

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SCALERP

SCALERP is a switch keyword for scaling previously calculated frequencies that appear in

the VIB section of input. This keyword is off by default. Frequencies that have already

been calculated with the FREQSCALE option are scaled, and therefore this option would

not be required. Frequencies that have been calculated without scaling, and then used

with the FREQSCALE option would require this keyword in order for the program to scale

them correctly.

SCLPT (NOSCLPT)

SCLPT is a switch keyword to specify the behavior of the force constant scaling option.

(Note: Details of the force constant scaling option can be found in the description of the

keyword FCSCALE).

If the keyword SCLPT is turned on along with the keyword FCSCALE, the potential surface

is actually scaled. The scaled force constant matrix will be used to obtain both the

frequencies and the normal mode eigenvectors in the normal mode analysis. Thus the

MEP is altered when FCSCALE is used with those force-constant involved reaction-path

following algorithms, such as VRP(ESD), Page-McIver, etc. Also, the first step on the

reaction path will be changed as well if the normal mode eigenvector with the imaginary

frequency is used to determine the direction of the first step.

However, if this switch is turned off using NOSCLPT, the force constant scaling is actually

just a way to change some of the frequencies. After frequencies are obtained from the

scaled force constant matrix, the un-scaled force constants are recovered. The normal

mode eigenvectors all come from the un-scaled force constants. Users should be aware

that the MEP is not altered using this strategy. The only quantity changed is the

frequencies. Those scaled frequencies will be used in the calculations of ZPE, vibrational

partition functions, and tunneling probabilities.

SDEBG1

SDEBG2

SDEBG1 and SDEBG2 are variable keywords used to specify the s limits of the interval on

the MEP at which to have debug information of the vibrational frequencies and

generalized normal-mode calculations output to unit fu6. The default unit is angstroms

and it can also be in bohr by specifying the keyword INPUNIT AU. (Note: the value of

SDEBG1 has to be smaller than SDEBG2).

Example: SDEBG1 0.499

SDEBG2 0.501

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SFIRST

SFIRST is a list keyword that allows a special step size for the first n steps. The user must

give the number of initial steps to be taken in each direction from the initial geometry,

including the initial step (NFSTEP) and the step size for each of these steps (FSIZE). The

default unit of FSIZE is angstroms and it can also be in bohr by specifying the keyword

INPUNIT AU. The defaults are NFSTEP = 0 and FSIZE = 1 10-5 ao.

Example: SFIRST

NFSTEP 10

FSIZE 0.0001

END

SIGN

SIGN is a variable keyword used to ensure the conventional definition of the sign of s,

s < 0 for the reactant side and s > 0 for the product side, is followed. The allowed

arguments for this variable are reactant and product: product if the unbound

eigenvector at the saddle point points toward the product side and reactant if the

eigenvector points toward the reactant side. The SIGN keyword is discussed further in

Section 7.B. The default is reactant.

Example: SIGN product

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SPECSTOP

SPECSTOP is a list keyword that may be used to specify the range over which the MEP is

to be computed. This keyword can function in conjunction with the SRANGE keyword

that is presented below. The SPECSTOP keyword may be used to limit the range over

which the MEP is calculated to a smaller range than that specified by the SRANGE

keyword. The MEP calculation will be stopped when the value of the potential energy

(VMEP) or the value of the vibrationally adiabatic ground-state potential energy (VaG)

becomes smaller than a critical value. This critical value is defined based on the values

of potential energy or zero-point-inclusive potential energy at the saddle point and

reactants or products. For example, if the VaG curve is chosen, the MEP will be

determined until the VaG(s) becomes smaller then the value calculated as: [(1-x) VaG(s=0)

+ x V+ZPE(R or P)] where V+ZPE(R or P) is the higher of the zero-point-inclusive

potential energy for the reactants and products, and x is equal to X/100 (X is the argument

of PERCENTDOWN subkeyword). Note that V+ZPE(R or P) is equivalent to VaG(R or P)

for a bimolecular reaction but not for an unimolecular reaction for which VaG(R or P)

does not include the zero-point-energy contribution of the reaction coordinate motion.

Similarly, if the VMEP curve is chosen, the MEP will be calculated until the VMEP(s)

becomes smaller then the value calculated as: [(1-x) VMEP(s=0) + x VMEP(R or P)] where

VMEP(R or P) is the higher of the zero-point-exclusive potential energy for the reactants

and products, and x is again equal to X/100 (X is the argument of PERCENTDOWN

subkeyword). Finally, the MEP limits can be chosen either on the fine grid (also called

gradient grid) or the save grid. In the current version of the code, this keyword cannot be

used if the calculation requires the use of a restart file (fu1, fu2, or fu3) or the use of an

electronic structure input file (fu29, fu30, fu31, or fu40). The valid keyword options are

defined below.

Option Description Default*

CURVE the curve on which comparison is made vag

(the options are vmep and vag)

POINT the grid on which the end point is chosen savegrid

(the options are savegrid and finegrid)

PERCENTDOWN percent down from the saddle point 50.

Example: SPECSTOP

CURVE vmep

POINT finegrid

PERCENTDOWN 63.4

END

Example (empty list, defaults only): SPECSTOP

END

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* These are the defaults if SPECSTOP is specified. If it is not specified, then PERCENTDOWN is

effectively infinity, i.e., only SRANGE is used to stop the reaction path calculation.

SPRNT

SPRNT is a variable keyword that, if PRINTSTEP is on, requires that |s| > SPRNT for any

reaction-path information to be printed. Default is 0. The default unit is angstroms and it

can also be in bohr by specifying the keyword INPUNIT AU.

Example: SPRNT 0.1

SRANGE

SRANGE is a list keyword needed to specify the limits on the reaction coordinate, s for

which the MEP is to be computed. These limits, SLM and SLP, are the ranges over which

the MEP is computed, i.e., SLM s SLP. The default unit is angstroms and it can also be in bohr by specifying the keyword INPUNIT AU. The default values are SLM = –1.0 ao and

SLP = +1.0 ao.

Example: SRANGE

SLP 1.50

SLM -1.75

END

SSPECIAL

SSPECIAL is a list keyword used to give all the special s values at which normal mode

analyses are to be performed. These values of s will be included in the Hessian grid. The

default unit is angstroms and it can also be in bohr by specifying the keyword INPUNIT

AU. The default is to not include any special s values. See keyword SSPECPR below.

Example: SSPECIAL

0.14

0.34

-0.76

END

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SSPECPR

SSPECPR is a switch keyword that works in conjunction with SSPECIAL. It turns on the

printing of generalized normal mode vibrational energies, frequencies, and eigenvectors

for the special s values regardless of whatever other print keywords are specified. The

default is off.

SSTOR

SSTOR is a list keyword that specifies the parameters used for the torsional-potential

anharmonicity calculations along reaction path by the SS-T method. Note that when only

a single structure among all conformational structures is considered, the MS-T method is

reduced to the SS-T method as described in Section 10.O. The SSTOR keyword also turns

on the SS-T calculations along reaction path. The valid keyword options are defined

below.

Option Description Default*

MTOR local periodicities of torsions, i.e. M j,t values no default

Example: SSTOR

MTOR 3 3 3 3

END

SSTEP

SSTEP is a variable keyword that specifies the step size along the mass-scaled MEP for

following the gradient of V, except that the first n steps can be different (see SFIRST). The

default unit is angstroms and it can also be in bohr by specifying the keyword INPUNIT

AU. The default is 5 10-4 ao.

Example: SSTEP 0.0001

Note that SSTEP is ignored if POTENTIAL = unit30, unit31, or unit40 is specified in the

GENERAL Section. See Section 9.C.

SYMMETRY (NOSYMMETRY)

SYMMETRY is a switch keyword that specifies that the reaction path is symmetric. When

this is turned on only one direction of the MEP from the saddle point is calculated, and

the MEP information from the other direction is obtained by reflection. Default is

NOSYMMETRY.

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VSCALE

VSCALE is a variable keyword for specifying the factor by which to scale the potential

energy along the MEP. If VSCALE is 0 or 1, no scaling is done. The default is 1.

Example: VSCALE 1

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12.A.8. TUNNEL section

The TUNNEL section contains the keywords that control the tunneling calculations. This

section is not needed if tunneling calculations are not desired. If this section is not

included then all defaults are ignored, and the default SCT, ZCT, and Wigner calculations

are not performed. For simplicity the keywords have been broken into two categories:

basic and large-curvature. This is only for clarity in the manual. The keywords in any of

these categories can be used in any order. Also for simplicity the keywords in each

category have been labeled as either common or other. The keywords labeled common

are those that might be expected to be found reasonably frequently in input files for

typical Polyrate runs. This labeling is only intended as an aid to the novice user. Again

an alphabetical glossary of all the keywords follows the two summary tables.

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Basic:

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Keyword Type Default Description

Common:

SCT switch on small-curvature tunneling

ZCT switch on zero-curvature tunneling

Others:

EMIN variable 0 cutoff E for computing percent

tunneling

QRST list not used quantized-reactant-state tunneling

HARMONIC switch on harmonic approximation

HARMWKB switch off harmonic-WKB approximation

SYMWKB switch off WKB and symmetric VaG

MODE variable required number of the selected vibrational

reaction-path mode

SRW variable required s value of the reactant

STATES variable all number of states included in

calculation

QUAD list no changes change quadrature parameters

NSEGBOLTZ variable 1 segments for Boltzmann integral

NSEGTHETA variable 1 segments for theta integral

NQE variable 40 quadrature points for Boltzmann

integral

NQTH variable 40 quadrature points for theta integral

SCTOPT list spline small-curvature tunneling options

LAGRANGE variable 4 Lagrange interpolation for eff

SPLINE switch on spline fit for interpolating eff

WIGNER switch on Wigner tunneling

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Large-curvature tunneling:

Keyword Type Default Description

Common:

ALLEXCIT switch on tunneling into all excited states

EXCITED variable 0.0 tunneling into nth excited state

LCT switch off large-curvature tunneling

LCTDETAIL list not used print extra details in LCT

calculations

Others

LCTOPT list not used large-curvature tunneling options

ILCT switch off interpolated LCG calculation

INTERPOLATE variable 4 order of interpolation (see glossary)

LCGMETHOD variable 4 method for LCT calculations

LCTRST switch off restart a previous LCT calculation

LCTSTR switch on store information from a LCT calculation for a possible restart

NGAMP variable 120 quadrature points for tunneling

amplitude

NGTHETA variable 120 quad. pts. for theta integral

NILCGPT variable 9 number of interpolated points at each tunneling energy

PRFREQ switch off print information (see glossary)

PRPROB switch off print uniform probabilities

RTPJAC switch off print information in pseudo-Jacobian coordinates

VADAVG switch off average the overlapping of two adiabatic potentials

VEFSRCH variable 999 search for possible nonadiabatic LCG4 regions

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Glossary of TUNNEL keywords

ALLEXCIT (NOALLEXCIT)

ALLEXCIT is a switch keyword that specifies that the large-curvature tunneling

calculations (see LCT) are to be performed with tunneling into all accessible excited states

in the LCT exit arrangement. Default is on. The opposite switch, NOALLEXCIT, specifies

that tunneling calculations be performed with tunneling into only the ground state.

Note that the maximum number of excited states is set by the MAXPS parameter in the

aamod.f90 file (see Subsection 5.A.2).

EMIN

EMIN is a variable keyword whose argument specifies the energy (in kcal/mol) that is the

cutoff point in computing the percent tunneling that comes from below Emin. The default

is 0.0.

Example: EMIN 48.35

EXCITED

EXCITED is a variable keyword whose argument is the state n. The LCT tunneling

calculation is performed with tunneling into up to the state with quantum number n,

where n = 0,1,.... Default is 0. The example below is for the case where tunneling will

be performed for the first excited state in the LCT exit arrangement (if accessible) as well

as for the ground state. Note that this keyword shouldn’t be used together with the

ALLEXCIT or NOEXCIT keyword.

Example: EXCITED 1

LCT3 or LCT4

One of these two keywords is compulsory if large curvature calculations are required.

The default is off. If LCT3 (the old LCT) or LCT4 (see Section 10.4. for details) are on,

then the COMP and OMT results (described in Section 6.I) are always calculated. Of

the two options (LCT3 and LCT4), LCT4 is recommended; LCT4, being the final

version, is usually just denoted LCT.

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LCTDETAIL

LCTDETAIL is a list keyword that prints extra details of the LCT calculations to Fortran

unit fu41 to fu47 files. The valid subkeyword options are defined below. See Section 14.

Option Description

state n n is the quantum number of the vibrational state (0 is the

ground state) for which information is to be printed. interval m m is the number of intervals of the energy grid the user wants

to print out for this particular quantum state; LB and UB are

lb1 ub1 the indices of the lower and upper bounds of the energy

lb2 ub2 grid interval, respectively.

:: lbm ubm

Example: LCTDETAIL

STATE 0

INTERVAL 2

20 22

30 32

STATE 1

INTERVAL 1

30 31

END

LCTGRID

This is a list keyword that specifies the grid to carry out the ILCT1D or ILCT2D

calculations. The valid options are defined below

Option Description

state n n is the quantum number of the vibrational state (0 is the ground

state) for which information is to be printed.

Npoints are the single point energy calculations carried out at each

tunneling energy and fitted to a spline. Npoints must be specified

with ILCT1D. The default is Npoints equal to 9.

NumberE NumberX The 2D grid to perform the ILCT2D calculation can be specified

here. NumberE are the number of tunneling energies and

NumberX is the number of points within each tunneling energy.

LCTOPT

LCTOPT is a list keyword that is used to set options for the large-curvature tunneling

calculations. If this keyword is used, then it is assumed that the large-curvature tunneling

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calculations are desired and LCT is automatically switched on. The valid options are

defined below.

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Option Description Default ILCT1D This switch keyword is used to calculate LCT3 or

LCT4 transmission factors. At each tunneling

energy performs a 1D spline under tension fit of the

nonadiabatic region. The number of energies

calculated along a given tunneling path is specified

in LCTGRID.

off

ILCT2D This switch keyword can be used either to calculate

LCT3 or LCT4 transmission factors, although we

recommend its use to evaluate only the latter. This

is a 2D spline under tension fit based on a grid of

tunneling energies and points along the tunneling

path for each tunneling energy. The grid is

specified in LCTGRID.

off

interpolate order of interpolation used for the LCG3 theta

integrals, the excited state potential, the vibrational

period, and the sine of the angle between the MEP

and the tunneling path.

4

lcgmethod Select the method for LCT calculations. Two

values are possible: 3 and 4, for LCG3 and LCG4

methods respectively.

4

lctrst restart a previous large curvature calculation from

unit fu48. This is useful to calculate LCT4

transmission factors from a previous LCT3 run.

off

lctstr store information in unit fu49 for a possible restart. on ngamp number of points for Gauss-Legendre quadrature

and trapezoidal rule in computing the total tunneling amplitude along the incoming trajectory in the LCG3 and LCG4 methods.

120

ngtheta number of points for Gauss-Legendre quadrature in

computing the theta integral over the straight-line

tunneling path in the LCG3 and LCG4 methods

120

prfreq print information in fu22 file about the frequency of

the mode p(s), the classical energy VMEP(s), and the

vibrationally adiabatic potential energy as a

function of s and np(Va(np,s)), and all the

uniformized probabilities at each np.

off

prprob print all uniformized probabilities at each np to fu22 off rtpjac print the MEP and representative tunneling path

turning points in mass-scaled pseudo-Jacobian

coordinates to fu24

off

vadavg average the overlapping of two adiabatic potentials

instead of choosing the minimum of them.

off

vefsrch numb search for possible nonadiabatic LCG4 regions in

totally adiabatic LCG3 regions. The search starts

from that tunneling energy until numb

0

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Example: LCTOPT

lctrst

ngamp 120

ngtheta 120

END

QRST

QRST is a list keyword that is used to specify the options for the quantized-reactant-state

tunneling calculations. This option should only be used with unimolecular reactions. It

is described in Refs. 8 and 37 of Sect. 21. Be sure that MXWKB is large enough if you use

this (See Section 5.A.2. MXWKB must be greater than or equal to the total number of

energy levels.) STATES subkeyword determines the number of quantized reactant states to

be included in the tunneling calculations. The options are all (all possible states are

included in the calculation), 0 (only the vibrational ground state will be considered), 1

(only the ground state and the first vibrational states will be considered), etc. STQVIB

subkeyword determines the number of quantized reactant states to be included in

calculation of the reactant vibrational partition function. The options are all (all

possible states are included in the calculation), and samet (the number of states used for

calculating the reactant vibrational partition function is the same as the number of states

used for tunneling contributions). The valid options are defined below.

Option Description Default harmonic use the harmonic approximation to determine the energy on

levels of the reaction-path mode

harmwkb between the reactant and saddle point use the WKB off

approximation to find the energy levels but use the

harmonic potential as the effective potential to the left

of the reactant

symwkb use the WKB approximation to find the energy levels and off

assume that the effective potential is symmetric with

respect to the reactant mode the number of the selected vibrational reaction-path mode

required

srw the value of the reaction coordinate at the position of the required

reactant. The default unit is angstrom and it can also be

in bohr by specifying the keyword INPUNIT AU.

states the number of quantized reactant states to be included all

in the tunneling calculation stqvib the number of quantized reactant states to be included all

in the vibrational partition function calculation

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Example: QRST

SYMWKB

STATES 5

MODE 3

SRW -2.42

STQVIB all

END

QUAD

QUAD is a list keyword that is used to specify the Gauss-Legendre quadrature points in

each segment used in computing the Boltzmann average (NQE) and theta integrals (NQTH)

in the tunneling calculations. The valid options are defined below.

Option Description Default

nqe number of Gauss–Legendre quadrature points in each 40

segment to be used for computing the Boltzmann average

in the tunneling calculations; allowed values are 2-7, 9,

10, 12, 15, 20, 30, and 40

nqth number of Gauss–Legendre quadrature points in each 40

segment to be used for computing the theta integrals in the

tunneling calculations; allowed values are 2-7, 9, 10,

12, 15, 20, 30, and 40 nsegboltz number of equal segments for integrals that average the 1

energy–dependent tunneling probabilities over a Boltzmann

distribution of energies

nsegtheta number of equal segments for the theta integrals 1

Example: QUAD

nqe 30

nqth 30

nsegboltz 2

nsegtheta 2

END

SCT (NOSCT)

SCT is a switch keyword that specifies that small–curvature tunneling calculations be

performed. Default is SCT.

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SCTOPT

SCTOPT is a list keyword that is used to specify the method for interpolating the effective

mass for the small–curvature tunneling calculations. See Section 10.E. The default is

SPLINE. The valid options are defined below.

Option Description Default

lagrange n Lagrangian interpolation of order n is used to interpolate 4

µeff(s)

spline spline fit is used to interpolate µeff(s) on

Example: SCTOPT

lagrange 5

END

WIGNER

WIGNER is a switch keyword that specifies that the Wigner transmission coefficient be

computed. Default is on because it is inexpensive, but it is not a reliable method. In the

current version of POLYRATE, this option cannot be turned off.

ZCT (NOZCT)

ZCT is a switch keyword that specifies that zero–curvature tunneling calculations be

performed. Default is ZCT.

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12.A.9. RATE section

The RATE section contains the keywords that control the rate constant calculations. This

section is not needed if rate constants are not desired. If this section is not included then

all defaults are ignored, and the default CVT and TST calculations are not performed. For

simplicity the keywords have been broken into three categories: basic, methods, and

print. This is only for clarity in the manual. The keywords in any of these three

categories can be used in any order. Also for simplicity the keywords in each category

have been labeled as either common or other. The keywords labeled common are those

that are found in most input files for a standard Polyrate run. This labeling is only

intended as an aid to the novice user. Again an alphabetical glossary of all the keywords

follows the three summary tables.

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Basic:

Keyword Type Default Description

Common:

BOTHK switch on forward and reverse rate constants

EACT list not used activation energy calculation

REVKEXP variable 0 scale factor for reverse rates

SIGMAF variable 1 sym. factor for forward reaction

SIGMAR variable 1 sym. factor for reverse reaction

TEMP list see below temperatures for rate calculations

Others:

ANALYSIS list not used detailed analysis of TST/CVT ratio

EDGEOK switch on continue calculation even if Gmax is near end of grid

FORWARDK switch off forward rate constant only

GSPEC list not used special grid for G calculation

SMAX variable 1.0 ao max. s for special grid

SMIN variable -1.0 ao min. s for special grid

GTEMP list not used special grid for G calc. for given T

GTLOG switch off free energy of activation by logarithms

STATE variable therm thermal or state-selected rate constant

STATEOPT list thermal options for STATE keyword

SPTOPT list options for simple pert. theory

CORIOLIS switch off include Coriolis term

PRINT switch off extra data printed out

VPFEXP variable 0 scale factor for vibrational partition function

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Methods:

Keyword Type Default Description

Common:

CVT switch on canonical VTST

Others:

TST switch on conventional transition state theory

MUVT switch off microcanonical VTST

MUVTOPT list options for VT

FIT variable gas53 primary and secondary fits

NITER variable 30 Gauss-Laguerre quadrature

PRENERGY variable 0 # of energies on the grid to print

SLOWER variable 0.0 lower limit of MEP for searching

SUPPER variable 0.0 upper limit of MEP for searching

CUS variable off canonical unified statistical model

US switch off unified statistical calculation

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Print:

Keyword Type Default Description

Others:

PRDELG switch off print free energy curve

PRPART variable not used print reactant, product, and saddle point partition functions

PRVIB list not used region to print extra vib mode info

SX variable 0.0 s at beginning of desired region

SY variable 0.0 s at the end of desired region

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Glossary of RATE keywords

ANALYSIS

ANALYSIS is a list keyword used to specify the temperatures (in Kelvin) at which a

detailed analysis of the conventional TST/CVT ratio is to be performed. The default is

not to do a detailed analysis at any temperature. (Note: the rate constant must be

computed at all temperatures on this list; see the TEMP keyword.)

Example: ANALYSIS

298.

400.

800.

END

BOTHK (NOBOTHK)

BOTHK is a switch keyword that specifies that both the forward and reverse rate constants

and the equilibrium constant are to be calculated. If NOBOTHK is specified no rate

constants are computed; use FORWARDK if only the forward rate constant is desired. The

default is BOTHK. (See REVKEXP for scaling the output for the reverse rate constant.)

CUS (NOCUS)

CUS is a variable keyword that specifies that rate constants should be calculated with the

canonical unified statistical model. See Ref. 51 in Sect. 22. The input argument of this

keyword indicates the maximum number of local maxima in the free energy of activation

vs. reaction coordinate profiles that should be included at each temperature. If the

number of local maxima that are found is less than this argument, then all maxima are

used. The CUS calculations will also include the lowest local minimum between any pair

of included local maxim. When the argument of CUS equals 1, the CUS result is exactly

the same as CVT. The default is NOCUS.

Example: CUS 2

CVT (NOCVT)

CVT is a switch keyword that specifies that generalized transition state theory and

canonical variational theory rate constants be calculated. The default is CVT. If NOCVT is

specified and NOTST is not specified, rate constants will be calculated but only at the

conventional-TST level. In this case, the calculations are carried out in subprogram

TSRATE (as opposed to RATE or GIVTST). TSRATE does not include anharmonicity.

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EACT

EACT is a list keyword used to specify the pairs of temperatures (in Kelvin) for which to

compute Arrhenius activation energies (maximum of 10 pairs) from the calculated rate

constants. Each line should first give the lower temperature and then the upper

temperature for the pair. The default is not to compute any activation energies. (Note:

the rate constant must be computed at all temperatures in this list; see the TEMP keyword.)

Example: EACT

298. 400.

400. 600.

END

EDGEOK (NOEDGEOK)

EDGEOK is a switch keyword that specifies that the calculation be continued even if Va or

GICVT is near an end point, i.e., even if the grid does not appear wide enough to find

variational transition states. The default is EDGEOK.

FORWARDK (NOFORWARDK)

FORWARDK is a switch keyword that specifies that only the forward rate constant be

calculated. If FORWARDK is specified, equilibrium constants will not be computed. The

default is NOFORWARDK.

GSPEC

GSPEC is a list keyword that is used to specify that the generalized free energy of

activation profile only be computed for the range SMIN s SMAX for all temperatures.

The default is to compute the free energy curve over the entire range of s. The default

unit is angstroms and it can also be in bohr by specifying the keyword INPUNIT AU. The

defaults for the options are SMAX = 1 ao and SMIN = -1 ao.

Example: GSPEC

SMAX 1.50

SMIN -0.05

END

GTEMP

GTEMP is a list keyword that is used to specify that the generalized free energy of

activation profile be computed over a different range of s for each temperature. Each

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entry in the list should contain the temperature in Kelvin and then SMAX and SMIN (in

bohr) for that temperature. The default is to compute the free energy curve over the

entire range of s. The default unit is angstroms and it can also be in bohr by specifying

the keyword INPUNIT AU. The defaults for the options are SMAX = 1 ao and SMIN = -1 ao.

Example: GTEMP

298. 1.50 -0.10

400. 1.00 -0.25

END

GTLOG (NOGTLOG)

GTLOG is a switch keyword that specifies that the generalized free energy of activation

should be calculated by using the logarithms of the vibrational partition functions. This

type of calculation is preferred when the vibrational partition function has an extremely

small value (as may be the case for very low temperatures and/or for very big systems

because we put the zero of energy for the partition coefficient at the lowest value of the

potential rather that at the zero point energy). The default is NOGTLOG.

MUVT (NOMUVT)

MUVT is a switch keyword that specifies that VT rate constants should be calculated.

The default is NOMUVT if US and MUVTOPT are off, and the default is MUVT if US is on or

MUVTOPT is given.

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MUVTOPT (NOMUVTOPT)

MUVTOPT is a list keyword that is used to set options for the VT calculation. If

MUVTOPT is given then it is assumed that the VT calculation is desired and the default

for MUVT becomes on. The valid options are defined below.

Option Description Default

niter number of Gauss-Laguerre quad. pts. for computing VT rate 30

constants

prenergy number of energies on the grid to be printed out; PRENERGY must 0

be £ min 6,niter

slower lower limit, respectively, of the region of the MEP over 0.0

which the GT minimum of NVT will be searched for. (This is

only specified if one wishes to limit the search. Leave set to the

default of zero to search over the entire s range.) The default

unit is angstroms and it can also be in bohr by specifying the

keyword INPUNIT AU.

supper upper limit, of the region of the MEP over which the GT

minimum of N will be searched 0.0

for. (This is only specified if one wishes to limit the search.

Leave set to the default of zero to search the entire s range.)

The default unit is angstroms and it can also be in bohr by

specifying the keyword INPUNIT AU. fit variable that specifies the degree of the primary and secondary gas53

fits. The allowed values are given below. For a gas-phase reaction,

gas53 is the recommended value, and for a reaction at a gas-solid

interface, gsolid13 is recommended. Sometimes there is a numerical

problem with the 5-point fit; in such a case it is recommended to use

gas31 rather than gas53.

value primary secondary phase

gas53 5 3 gas

gas15 1 5 gas

gas35 3 5 gas

gas31 3 1 gas

gas13 1 3 gas

gsolid13 1 3 gas-solid interface

gsolid15 1 5 gas-solid interface

gsolid31 3 1 gas-solid interface

gsolid53 5 3 gas-solid interface

Example: MUVTOPT

niter 40

END

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PRDELG (NOPRDELG)

PRDELG is a switch keyword that specifies that G(T,s) be printed to fu6. Default is

NOPRDELG.

PRPART (NOPRPART)

PRPART is a variable keyword. Its argument specifies that the reactant and product (rp)

partition functions, the saddle point (t) partition functions, or the reactant, product, and

saddle point (rpt) partition functions should be printed to fu6. When the reactant

partition function is printed for a gas-phase unimolecular reaction the internal free energy

of reactant is also printed. The default is not to print any partition functions or free

energies at the stationary points.

Example: PRPART rp

PRVIB

PRVIB is a list keyword that is used to specify the initial and final s values, with keywords

sx and sy respectively, that delineate a region for which extra vibrational mode and Qvib

information be printed to fu6. The default is no extra printing. The default unit is

angstroms and it can also be in bohr by specifying the keyword INPUNIT AU.

Example: PRVIB

SX 0.0

SY 0.6

END

REVKEXP

REVKEXP is a variable keyword whose argument specifies the value n in the scale factor

10-n for the reverse rate constant. The final rate will be calculated in units of 10-n cm3

molecule-1 s-1 if there are two products or in units of 10-n s-1 if there is one product.

Default is n = 0, i.e., a scale factor of 1.

Example: REVKEXP 10

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SIGMAF

SIGMAF is a variable keyword whose argument specifies the number of equivalent ways

for forming the GTS for the forward reaction. The default value is 1.

Example: SIMGAF 1

SIGMAR

SIGMAR is a variable keyword whose argument specifies the number of equivalent ways

for forming the GTS for the reverse reaction. The default value is 1.

Example: SIMGAR 1

STATE

STATE is a variable keyword whose argument specifies if this is to be a thermal or state–

selected rate constant calculation. The default is therm. The valid arguments are:

Option Description

therm thermal run

adiab adiabatic state-selected; STATEOPT is required

diab x diabatic state-selected; x is the value of the reaction

coordinate at which the adiabatic/diabatic switch is made;

STATEOPT is required

Example: STATE adiab

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STATEOPT

STATEOPT is a list keyword that is used to specify how each mode in each reactant,

product, and transition state is to be treated. By default each mode is treated thermally.

The user needs to specify each mode explicitly that is to be restricted to the ground state

or first excited state as shown below. Each input line in the list requires:

reatyp nmode modtyp

The allowed values of the variable reatyp are:

Value Description

react1 reactant #1

react2 reactant #2

prod1 product #1

prod2 product #2

ts transition state and along the reaction path

switts reaction path after the adiabatic/diabatic switch (see

STATE)

nmode is an integer specifying the vibrational mode number

The allowed values of the variable modtyp are:

Value Description

thermal mode is thermal (default)

ground mode is restricted to the ground state

first mode is restricted to the first excited state

Example: STATEOPT

react1 1 ground

react2 1 first

prod1 1 thermal

prod1 2 ground

prod1 3 first

ts 4 ground

ts 5 first

switts 4 first

switts 5 ground

END

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TEMP

TEMP is a list keyword used to specify the temperatures (in Kelvin) at which rate

constants be computed. Unless NOBOTHK or FORWARDK is selected the equilibrium

constants will also be calculated at these temperatures. The default is to compute the rate

constants at 7 temperatures: 200, 300, 400, 600, 1000, 1500, and 2400.

Example: TEMP

298.

400.

600.

800.

END

TST (NOTST)

TST is a switch keyword that specifies that the conventional transition state theory rate

constants be calculated. The default of TST is on. If any other rate constants are

calculated, i.e., CVT, ICVT, US, or VT, then the conventional rate constants will

automatically be calculated (NOTST will have no effect) except when VRC is turned on

US (NOUS)

US is a switch keyword that specifies that unified statistical rate constants be calculated.

If US is on, then MUVT is automatically turned on. The default of US is off, which is the

same as specifying NOUS.

VPFEXP

VPFEXP is a variable keyword that that specifies that the total vibrational partition

functions be scaled by 10n where n is the argument. The default is no scaling.

Example:

VPFEXP 2

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12.B. General description of file fu29 input

File fu29 is only needed if IVTST0 or IVTST1 is specified in the GENERAL section of the

unit fu5 input. This unit contains input data for IVTST rate calculations. The first section

of this input file must be *IVTST. All input sections must start with the section name

preceded by an “*”, and must end with an END line (a line containing “end”). Keywords

and input data for each section are discussed further in the rest of this subsection. Sample

inputs can be found in several test runs described in Section 16.

Section Name Description

*E1GEOM Cartesian coordinates of the extra point on the MEP

*E1GRAD Cartesian gradient vector of the extra point on the MEP

*E1HESS Cartesian Hessian of the extra point on the MEP

*IVTST general data for IVTST calculations (must come first)

*P1FREQ frequencies of the 1st product

*P2FREQ frequencies of the 2nd product

*P1HESS Cartesian Hessian of the 1st product

*P2HESS Cartesian Hessian of the 2nd product

*R1FREQ frequencies of the 1st reactant

*R2FREQ frequencies of the 2nd reactant

*R1HESS Cartesian Hessian of the 1st reactant

*R2HESS Cartesian Hessian of the 2nd reactant

*TSHESS Cartesian Hessian of the saddle point

*TSFREQ frequencies of the saddle point

When IVTST0 is specified, the user can choose between giving the Hessian or the

frequencies for the stationary points (reactants, saddle point and products) according to

the kind of information available for the system. When running an IVTST1 calculation

the use of Hessians for the stationary and extra points is required, since this information

is needed in order to calculate the SCT transmission factors.

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12.B.1. E1GEOM Section

The E1GEOM section of the file fu29 input is used to give the Cartesian coordinates of the

extra point on the MEP. This section is only needed for first-order IVTST calculations.

Example: *E1GEOM

0.000000 0.000000 0.000000

0.456364 1.749560 0.000000

1.808100 0.000000 0.000000

END

12.B.2. E1GRAD Section

The E1GRAD section of the file fu29 input is used to give the Cartesian gradient vector of

the extra point on the MEP. This section is only needed for first-order IVTST

calculations.

Example: *E1GRAD

0.000000 0.000000 0.000000

0.056364 0.009560 0.000000

0.008100 0.000000 0.000000

END

12.B.3. E1HESS, P1HESS, P2HESS, R1HESS, R2HESS, and TSHESS sections

The E1HESS, P1HESS, P2HESS, R1HESS, R2HESS, and TSHESS sections of file fu29 input are

used to give the Cartesian Hessian matrix of the extra point on the MEP, products,

reactants, and the transition state in packed form, respectively. The E1HESS section is

only needed for first-order IVTST calculations.

Example: *E1HESS

0.000000

0.056364 0.009560

0.008100 0.000000 0.000000

0.008100 0.000000 0.000000 0.080100

0.008100 0.000000 0.000000 0.080100 0.080100

0.008100 0.000000 0.000000 0.080100 0.080100

0.080100

END

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12.B.4. IVTST Section

The IVTST section of the file fu29 input is used to give general data for IVTST

calculations. The table below lists all valid subkeywords for the IVTST section. A

detailed explanation of each keyword is given alphabetically in the glossary below.

Keyword Type Default Description

BARRI variable required classical barrier height in kcal/mol

DELTAE variable required classical energy of the products in kcal/mol

DELEX1 variable not used the classical energy of the extra point in kcal/mol (only needed for the IVTST1)

PRINT switch 0 output control

SEX1 variable not used the reaction coordinate at the extra point in atomic units (only needed IVTST1)

UNITS switch 0 units for geometry, gradient, and Hessian matrix

Glossary of IVTST keywords

BARRI

BARRI is a keyword that specifies the classical barrier height in kcal/mol. In case a

conversion of units is required for obtaining this value in kcal/mol, the conversion factor

used should be the same as that internally employed by Polyrate as specified in the

percon.inc file.

Example: BARRI 5.0

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DELTAE

DELTAE is a keyword that specifies the classical energy of the products relative to the

classical energy of the reactants in kcal/mol. This is a required keyword. In case a

conversion of units is required for obtaining this value in kcal/mol, the conversion factor

used should be the same as that internally employed by Polyrate as specified in the

percon.inc file.

Example: DELTAE -5.0

DELEX1

DELEX1 is a keyword that specifies the classical energy of the extra point relative to the

classical energy of the reactants in kcal/mol. This keyword is only needed for first-order

IVTST calculations.

Example: DELEX1 -4.4

PRINT

PRINT is a keyword for output control: 0—normal (default), 1—debug.

Example: PRINT 1

SEX1

SEX1 is a keyword that specifies the reaction coordinate at the extra point in bohr. This

keyword is only needed for first-order IVTST calculations.

Example: SEX1 0.1

UNITS

UNITS is a keyword that specifies the units for the geometry, gradients and Hessian

matrix: UNITS = 0: The geometry will be in bohrs, and both the gradients, and the

Hessian matrix will be in mass-scaled atomic units (default). UNITS = 1: The geometry

will be in mass-scaled Å, and both the gradient vectors and the Hessian matrix will be in

non-mass-scaled atomic units.

Example: UNITS 0

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12.B.5. P1FREQ, P2FREQ, R1FREQ, R2FREQ, and TSFREQ sections

The P1FREQ, P2FREQ, R1FREQ, R2FREQ, and TSFREQ sections of the file fu29 input are used

to give the frequencies (in cm–1

) of the product and reactant molecules and the saddle

point, respectively. The imaginary frequency of the saddle point must be the last input

value in the TSFREQ section.

Example: *R1FREQ

2000.0 1000.0

END

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12.C. General description of file fu30 input

File fu30 contains the information typically obtained from electronic structure

calculations which is required for performing a direct dynamics calculation (see Section 9

for a detailed description of this capability). This option is selected by setting the

keyword POTENTIAL in the ENERGETICS section equal to unit30.

File fu30 is organized in the following way: 1) a one-line title; 2) 2 lines with numerical

options for routing and output; and 3) several blocks of data containing the specific

information provided for each point on the reaction path according to the options selected

(s, V, frequency matching data, Cartesian coordinates, gradient, frequencies or Hessian

matrix, anharmonicity data, curvature component data, etc.).

The user should be aware that gradients provided in the fu30 file must correspond to

structures that have not been arbitrarily reoriented along the reaction path in order to

obtain meaningful results in the calculation of the curvature components BmF. See

Section 9 for a fuller discussion of this issue.

A record-by-record description (where a record is one or more lines) of the structure of

the FORTRAN unit fu30 follows. If the keyword POTENTIAL = unit30, Polyrate can

be used with the dummy potential energy surface file provided, dumpot.f, since the

potential routines SURF and SETUP will not be called.

Record Format

(Records 1 and 2 are read in subprogram RPHSET)

1 One-line title (80A1)

2 Routing and output options (LOPT(I), I = 1, 40) (*)

LOPT(1) LEVEL OF PRINT

0, print out only titles and options

= 1, also print out summary

= 2, also echo input as it is read

= 3, also print out intermediate information about

fitting exponential functions and print

out interpolated results each time

RPHINT is called

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4, also print out debugging information in

exponential fitting

LOPT(2) MAXIMUM NUMBER OF POINTS USED IN LAGRANGE

INTERPOLATION IN THE PROCEDURE OF SUBSECTION

9.C.

= –1, use IVTST-M for interpolating. See Sect.

9.C.

Note: When using file fu30, the user cannot select any options for the IVTST-M

calculation; it will be performed according to the default options, and the number of

gradient and Hessian points have to be the same and equal to NPTS (see below).

Therefore, only IVTST-M-NPTS/NPTS calculations are allowed. The curvature

components will be interpolated using a value of 3 for the exponent in the mapping

function. For unimolecular reactions or reactions with wells, a cubic polynomial

fitting to V is done previous to its spline fitting, taking a step of 0.01 a0 along the

lowest frequency mode for performing this fitting. The only way to change any of

these options or to use a different number of gradient and Hessian points is by using

the fu31 input file, which is specifically designed for IVTST-M calculations.

LOPT(3) OPTIONS FOR COORDINATES (X) AND GRADIENTS (DX)

-2, X in mass-scaled Cartesians, DX in

unscaled Cartesians

= -1, X in unscaled Cartesians, DX in mass–

scaled Cartesians

= 0, X and DX in unscaled Cartesians

= 1, X and DX in mass-scaled Cartesians

= 99, X in unscaled Cartesians, -DX in mass-

scaled Cartesians

= 100, X in unscaled Cartesians, -DX in

unscaled Cartesians

Note: DX denotes the gradient, and -DX denotes the negative of the gradient which

is the force. For dynamics calculations in Cartesian coordinates, the normalized

gradients (or forces) can be used without any effects on the results. However,

unnormalized gradients have to be used for the curvilinear option. Notice the

‘Cartesian Forces’ from GAUSSIAN formatted check point output file are actually

the Cartesian gradient components.

LOPT(4) OPTIONS FOR FREQUENCY OR HESSIAN MATRIX INPUT

There are three issues:

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(1) Are the frequencies read in from unit fu30, or are they

obtained by diagonalizing the Hessian matrix F or the

projected Hessian FP?

(2) If the frequencies are calculated from the Hessian, how is F

read in, in packed (triangular) form, in packed form with full

lines, or in unpacked (full matrix) form?

(3) What coordinate system was used in computing F?

LOPT(4) (1) (2) (3)

-2, diagonalization packed mass-scaled coordinates

= -1, diagonalization packed unscaled coordinates

= 0, frequencies are

read

= 1, diagonalization full matrix unscaled coordinates

= 2, diagonalization full matrix mass-scaled coordinates

Notes: (1) If LOPT(4) 0, the choice of coordinates (mass-scaled or not) must be

consistent with LOPT(3).

(2) If the Hessian is read, the code assumes it is the non-projected Hessian.

(3) Packed full lines means 5 elements per line; whereas packed triangular

means F(1,1) on first line, F(2,1) and F(2,2) on second line, etc.

LOPT(5) ANHARMONICITY INPUT

0, no anharmonicity data read

= 1, read the third derivatives k3 with respect to the

normal coordinates at each grid point

2, also read the fourth derivatives k4 with respect

to the normal coordinates at each grid point

LOPT(6) OPTIONS FOR CURVATURE COMPONENT BmF INPUT

0, BmF are set to zero everywhere

= 1, BmF are read directly

= 2, BmF are computed. Derivative of the gradient

with respect to s is obtained from a quadratic fit

of the gradient at three points on the basic input

grid (defined in Section 9.C), with the middle

point being the current point on the Hessian

grid.

= 3, BmF are computed. Derivative of the gradient is

computed by one-sided finite difference, using

the gradient on the basic input grid and a

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gradient input at one extra point near the basic

input grid point.

4, BmF are computed. Derivative of the gradient is

computed from a quadratic fit obtained using

the gradient on the basic input grid and

gradients input at an extra point on each side of

the basic input grid point.

Note: For LOPT(6) > 1, BmF are computed and require the coefficient matrix

from the diagonalization of the Hessian matrix. Therefore, LOPT(4) must be

nonzero if LOPT(6) > 1.

LOPT(7)-LOPT(40): Not used in the present version of POLYRATE.

Loop over records 3 through 14 for each reactant species and then for each product

species. Records 3-25 are read in subprogram RPHRD2.

3 One-line title (80A1)

4 S, V (*)

S = value of s in bohrs at reactant (or product). This only has

meaning for a unimolecular and/or association reaction, for which s

is finite at the reactant and/or product; otherwise S is ignored.

V = potential (in atomic units) at reactants (or products).

For an atomic reactant or product, skip records 5 through 14, add a blank line after

record 4, and then continue with the next species.

5 (IFREQ(I),I = 1, NFREQ) (*)

IFREQ = indices for reordering frequencies, anharmonicities, and

curvature components in the interpolation table for the reactant or

product species, in order to make the ordering consistent with that at

the saddle point and/or along the MEP.

Note: Index 1 corresponds to the largest frequency at the saddle

point, index 2 to the second largest frequency, and so on. The

imaginary frequency is not included in this ordering.

Note that this matching is not necessary if you are just calculating

conventional TST reaction rates.

NFREQ is the number of bound vibrational modes for the species.

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For a Morse diatom reactant or product, read record 6; otherwise go to record 7.

6 SGN

SGN = sign used to multiply the third derivative of the diatomic

potential. This can be used to make the sign of the third derivative

of this mode in the asymptotic reactant or product region match up

with the correlating mode in the interaction region. This ensures a

smooth extrapolation into the asymptotic region.

For a Morse diatom reactant or product, skip records 7 through 14. If LOPT(4) = 0

(frequencies directly input), skip records 7 and 8.

7 One-line title (80A1)

8 N records of (F(I,J),J = 1, JF) N records of (*)

F = Hessian matrix (in atomic units) for the reactant or product

species. Second derivatives are with respect to Cartesian

coordinates; LOPT(4) determines whether the coordinates are mass-

scaled or not. JF = N for LOPT(4) > 0 and JF = I for LOPT(4) < 0,

where N = 3*NRATOM, NRATOM = number of atoms in the species,

and I indexes the N records in this set (I = 1,..., N).

If LOPT(4) 0, skip records 9 and 10.

9 One-line title (80A1)

10 (FREQ(I), I = 1, NFREQ) (*)

FREQ = vibrational frequencies (in atomic units) for the reactant

or product species.

If LOPT(5) < 1 (no anharmonicity), skip records 11 through 14.

11 One-line title (80A1)

12 (XK3(I), I = 1, NFREQ) (*)

XK3 = third derivatives of V with respect to motion along the

normal coordinates for the reactant or product species.

If LOPT(5) < 2 (just third derivatives), skip records 13 and 14.

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13 One-line title (80A1)

14 (XK4(I), I = 1, NFREQ) (*)

XK4 = fourth derivatives of V with respect to motion along the normal

coordinates for the reactant or product species.

After each reactant or product species except for the last product, go back to record 3.

After the last product, go to the next record.

If there is no saddle point, skip records 15 through 27.

15 One-line title (80A1)

16 S, V (*)

S = a dummy quantity and is ignored.

V = potential (in atomic units) at the saddle point.

17 (IFREQ(I), I = 1, NFREQ) (*)

These quantities are the same as in record 5, but now they refer to

the bound vibrational modes of the saddle point. NFREQ is now

the number of bound vibrational modes of the saddle point.

If LOPT(4) = 0, skip records 18 and 19.

18 One-line title (80A1)

19 N3 records of (F(I,J), J = 1, JF) N3 records of (*)

These quantities are the same as in record 8, but now they refer to

the saddle point. JF = N3 for LOPT(4) > 0 and JF = I for LOPT(4) <

0, where I indexes the N3 records in this set (I = 1,...., N3), and

where N3 = 3*NATOM, NATOM = number of atoms in the system.

If LOPT(4) 0, skip records 20 and 21.

20 One-line title (80A1)

21 (FREQ(I), I = 1, NFREQ) (*)

These quantities are the same as in record 10, but now they refer to

the bound vibrational modes of the saddle point.

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If LOPT(5) < 1 (no anharmonicity), skip records 22 through 25.

22 One-line title (80A1)

23 (XK3(I), I = 1, NFREQ) (*)

These quantities are the same as in record 12, but now they refer to

the bound vibrational modes of the saddle point.

If LOPT(5) < 2 (just third derivatives), skip records 24 and 25.

24 One-line title (80A1)

25 (XK4(I), I = 1, NFREQ) (*)

These quantities are the same as in record 14, but now they refer to

the bound vibrational modes of the saddle point.

If LOPT(4) 0, skip records 26 and 27.

Records 26-31 are read in subprogram RPHRD1.

26 One-line title (80A1)

27 WSTAR (*)

WSTAR = absolute value of the imaginary frequency at the saddle point.

If the reaction path is calculated, read records 28 to 63.

28 One-line title (80A1)

29 NPTS (*)

NPTS = number of s points along the MEP (not including the saddle point) at

which reaction-path Hamiltonian data is to be read (maximum of 200).

Unless only TST reaction rates are calculated, file fu30 must contain a

minimum of one point on each side of the saddle point. Unless NEXTPT is on,

these points must be arranged in order of increasing S.

Loop over records 30 through 52 NPTS times, from the lowest value of s to the highest

value of s. Records 30-50 are read in subprogram RPHRD2.

30 One-line title (80A1)

31 S, V (*)

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S = value of s (in bohr) at the grid location along the MEP.

V = potential (in hartrees) at s on the MEP.

32 One-line title (80A1)

33 (X(I), I = 1, N3) (*)

X = Cartesian coordinates of the GTS at s on the MEP.

N3 = 3*(number of atoms in the total system). Ordering is the same

as specified in the ATOM keyword of the FORTRAN unit fu5 data.

Note: LOPT(3) determines whether the coordinates are mass-scaled

or not.

34 One-line title (80A1)

35 (DX(I), I = 1, N3) (*)

DX = gradient vector (in atomic units) at s along the MEP. DX can

be the vector of derivatives of the potential with respect to the

Cartesian coordinates or it can be normalized. LOPT(3) determines

whether the coordinates are mass-scaled or not. Ordering is the

same as for X(I) in record 33.

Note: Some electronic structure codes print the force rather than

the gradient. Recall that the force is the negative of the gradient.

If LOPT(6) 2, skip records 36 through 41.

36 One-line title (80A1)

37 SB(1) (*)

SB(1) = value of s (in bohr) at a location along the MEP close to the

current grid point.

38 (DX(I), I = 1, N3) (*)

These quantities are the same as in record 35, but now they refer to the

location SB(1) on the MEP.

If LOPT(6) 3, skip records 30 through 41.

39 One-line title (80A1)

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40 SB(2) (*)

SB(2) = value of s (in bohr) at another location along the MEP close

to the current grid point.

41 (DX(I), I = 1, N3) (*)

These quantities are the same as in record 35, but now they refer to

the location SB(2) on the MEP.

42 (IFREQ(I), I = 1, NFREQ) (*)

These quantities are the same as in record 17, but now they refer to

the bound generalized normal modes of the current grid point along

the MEP.

If LOPT(4) = 0, skip records 43 and 44.

43 One-line title (80A1)

44 N3 records of (F(I,J), J = 1, JF) (*)

These quantities are the same as in record 19, but now they refer to

the current grid point along the MEP.

If LOPT(4) 0, skip records 45 and 46.

45 One-line title (80A1)

46 (FREQ(I), I = 1, NFREQ) (*)

These quantities are the same as in record 21, but now they refer to the

current grid point along the MEP.

If LOPT(5) < 1 (no anharmonicity), skip records 47 through 50.

47 One-line title (80A1)

48 (XK3(I), I = 1, NFREQ) (*)

These quantities are the same as in record 23, but now they refer to

the current grid point along the MEP.

If LOPT(5) < 2 (just third derivatives), skip records 51 and 52.

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49 One-line title (80A1)

50 (XK4(I), I = 1, NFREQ) (*)

These quantities are the same as in record 25, but now they refer to the

current grid point along the MEP.

If LOPT(6) = 1 (BmF are read), read records 51 and 52.

Records 51-63 are read in RPHRD1.

51 One-line title (80A1)

52 (BFS(I), I = 1, NFREQ) (*)

BFS = reaction-path curvature components (in atomic units) at the

current grid point along the MEP.

Return to record 30 until records 30 through 52 have been read NPTS times.

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12.D. General description of file fu31 input

This file is only needed if the POTENTIAL keyword of the ENERGETICS section of file fu5 is

equal to unit31. The input is in free format keyword style and is composed of several

sections. When unit31 is used, the code always uses the IVTST-M algorithm.

12.D.1. Section descriptions

Section Name Description

*GENERAL general data such as options for input and IVTST-M

*REACT1 information for the first reactant

*REACT2 information for the second reactant (if any)

*PROD1 information for the first product

*PROD2 information for the second product (if any)

*WELLR information for the well on the reactant side (if any)

*WELLP information for the well on the product side (if any)

*SADDLE information for the saddle point

*POINT information for a point along the MEP

Each section must appear once and only once except POINT, which has to appear at least

twice (since IVTST-M is not defined for less than one point on each side of the reaction

path). The POINT section should be repeated once for each of the nonstationary points

along the MEP. A saddle point is also required for carrying out an IVTST-M calculation.

Therefore, the fu31 input file cannot be used for reactions without a saddle point.

The program is insensitive to the order in which the points are entered. This is one of the

main differences between the fu31 input file and the fu30 and fu40 files. This allows us

to use an fu31 file written by means of the writefu31 option for the RESTART

keyword in the GENERAL section of the fu5 input file without any change. Another

difference is that Hessians are not required at each point; since the calculation of the

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reaction path always gives a value of the reaction coordinate, s, the energy, geometry, and

gradients, this information is required, but the Hessian information is not. This way, the

user can take advantage of the information calculated for points between two Hessian

points.

Since the IVTST-M calculation is always based on frequencies ordered in canonical

order, no frequency indexes are required. Moreover, since anharmonicity is not

supported for IVTST-M calculations, in the current version of POLYRATE, no anharmonic

data is allowed. From all other points of view, the fu31 input file is very similar to a fu30

or fu40 input file.

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12.D.2 GENERAL section

Keyword Type Default Description

GEOM list no changes change defaults for reading geometries

GRADS list no changes change defaults for reading gradients

HESSIAN list no changes change defaults for reading Hessians

INTMUEFF switch off interpolation of the exponent in the effective tunneling mass

KIES switch off recalculation of the s values

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Glossary of GENERAL keywords

GEOM

GEOM is a list keyword for selecting the units of the geometries input in the fu31 file. The

units are completely defined by a combination of two keywords; thus, if we want to input

the mass-scaled geometries in angstroms we will have to select both ms and ang. If one

of the options is not given, the default value is assumed.

Option Definition ang Geometries are given in Å.

au Geometries are given in atomic units (default).

ms Geometries are given in mass-scaled Cartesian coordinates.

uns Geometries are given in unscaled Cartesian coordinates (default).

Example: GEOM

ang

ms

END

GRADS

GRADS is a list keyword for selecting the units of the gradients (or forces) input in the

fu31 file. The units are completely defined by a combination of three keywords.

Option Definition

ang Gradients are given in Å.

au Gradients are given in atomic units (default).

ms Gradients are given in mass-scaled Cartesian coordinates.

uns Gradients are given in unscaled Cartesian coordinates

(default). forces Forces are given; the gradients are obtained from them.

grads Gradients are given (default).

Example: GRADS

ang

uns

forces

END

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HESSIAN

HESSIAN is a list keyword for selecting the units of the Hessian matrices input in the fu31

file. The units are completely defined by a combination of three keywords.

Option Definition

ang Gradients are given in Å.

au Gradients are given in atomic units (default).

ms Gradients are given in mass-scaled Cartesian coordinates.

uns Gradients are given in unscaled Cartesian coordinates (default).

full Full Hessian matrices are given.

packed Packed Hessian matrices are given (default).

Example: HESSIAN

full

END

If packed is selected, the lower triangular elements of F should be listed in order such

that F P i i jij = - +( ( ) )12

1 , where P(k) is element k of the input list and Fij is the

element of F in row i and column j. The number of elements listed per line is arbitrary.

Examples of both input forms for a 6 x 6 matrix is shown below:

Full matrix - example 1

F11 F12 F13 F14 F15 F16

F21 F22 F23 F24 F25 F26

F31 F32 F33 F34 F35 F36

F41 F42 F43 F44 F45 F46

F51 F52 F53 F54 F55 F56

F61 F62 F63 F64 F65 F66

Full matrix - example 2

F11 F12 F13 F14 F15 F16 F21 F22 F23

F24 F25 F26 F31 F32 F33 F34 F35 F36

F41 F42 F43 F44 F45 F46 F51 F52 F53

F54 F55 F56 F61 F62 F63 F64 F65 F66

Packed matrix - example 1

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F11

F21 F22

F31 F32 F33

F41 F42 F43 F44

F51 F52 F53 F54 F55

F61 F62 F63 F64 F65 F66

Packed matrix - example 2

F11 F21 F22 F31 F32 F33

F41 F42 F43 F44 F51 F52

F53 F54 F55 F61 F62 F63

F64 F65 F66

The order of the coordinates is explained in Section 12.E.1.

Note that GAUSSIAN94 writes the packed Hessian matrix in a slightly different way in the

standard output file, but the Hessian in the formatted checkpoint file (requested by their

FormCheck keyword) is in precisely the packed form accepted by Polyrate and so is

convenient for copying and pasting into Polyrate fu40 files.

Note that the exact F matrix is symmetric, but due to finite precision in computations, the

actual matrix one has to input is usually nonsymmetric. If one inputs a nonsymmetric full

matrix, the code uses the unsymmetric matrix. If a user wants the code to use a

symmetric matrix, we recommend taking an arithmetic average of Fij and Fji for the

resulting symmetrized elements in packed form.

INTMUEFF (NOINTMUEFF)

The interpolation of the effective mass for CD-SCSAG tunneling can be done in two

ways in an IVTST-M calculation: by means of the interpolation of the curvature

components and evaluation of the effective mass, or by means of the direct interpolation

of the effective mass, specifically, of the term inside the exponential of the equation 16 in

Ref. IVTST-M. The latter option can be selected by means of the INTMUEFF switch

keyword, but the former option (NOINTMUEFF) is recommended and it is set as the default

option.

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KIES (NOKIES)

In a calculation of kinetic isotope effects the values of the reaction coordinate, s,

calculated for one isotopomer are not valid for another isotopomer, since the values of s

are defined in a mass-scaled space. The KIES keyword allows the calculation of the

kinetic-isotope-effects-specific values of s. These values are calculated as the straight

line between two consecutive points in the isotope-specific mass-scaled space.

Therefore, if the KIES keyword is on, the values of s included in the fu31 input file will

only be used for ordering the points along the reaction path according to the standard

procedure: first the points with negative s, then the saddle point, and then the points with

positive s, ordered in increasing value of s. The geometries in file fu31 must be given in

unscaled coordinates (GEOM = uns). Nevertheless, if the calculation of new values of s

gives place to an permutation in the position of two points (which will not occur as a

consequence of just a change in an atomic mass) the program will not detect it, and the

interpolation will probably fail. The default is off (NOKIES) and its use is only

recommended for a KIE's calculation with RODS using a the reaction path calculated

with a different isotope.

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12.D.3. REACT1, REACT2, PROD1, PROD2, WELLR, WELLP, and SADDLE

sections

Keyword Type Default Description

VMEP variable (see Glossary) value of VMEP(s)

SMEP variable (see Glossary) value of s

GEOM list (see Glossary) geometries

GRADS list (see Glossary) gradients

HESSIAN list (see Glossary) Hessians

ENERXN variable (see Glossary) reaction energy

ENERSAD variable (see Glossary) barrier height

ENEWELLR variable (see Glossary) energy of the well on the reactant side of the reaction-path

ENEWELLP variable (see Glossary) energy of the well on the product side of the reaction-path

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Glossary of REACT1, REACT2, PROD1, PROD2, WELLR, WELLP, and SADDLE keywords

ENERSAD

ENERSAD is a variable keyword that indicates the value of the barrier height, in atomic

units (measured by taking the zero of energy at reactants). Its only acceptable position is

in the SADDLE section, where it is required.

ENERWELLR

ENERWELLR is a variable keyword that indicates the energy of the well on the reactant

side of the reaction path, in atomic units (measured by taking the zero of energy at

reactants). Its only acceptable position is in the WELLR section.

ENERWELLP

ENERWELLP is a variable keyword that indicates the energy of the well on the product side

of the reaction path, in atomic units (measured by taking the zero of energy at reactants).

Its only acceptable position is in the WELLP section.

ENERXN

ENERXN is a variable keyword that indicates the reaction endoergicity, in atomic units

(measured by taking the zero of energy at reactants). Its only acceptable positions are the

PROD2 section for reactions with two products, and the PROD1 section for reactions with

one product.

GEOM

GEOM is a list keyword that specifies the Cartesian coordinates at the current grid point.

Its only acceptable position is the POINT sections, where it is required; the geometries for

the stationary points are read from the fu5 input file.

GRADS

GRADS is a list keyword that specifies the Cartesian gradients (or forces) at the current

grid point. Its only acceptable position is the POINT sections, where it is required, since

the gradients for the stationary points are assumed to be zero.

HESS

HESS is a list keyword that specifies the Cartesian Hessian matrices. It is required in all

the REACT1, REACT2, PROD1, PROD2, WELLR, WELLP, and SADDLE sections (if they exists

and they are not atomic species). It is not required in all the POINT sections, but there

must be at least one POINT section with Hessian information on each side of the reaction

path.

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SMEP

SMEP is a variable keyword that specifies the value of the reaction coordinate s at the

current grid point, in mass-scaled atomic units. This keyword is required and only

accepted in the POINT sections; for reactants, products, and wells the value of s is

calculated as described in Ref. 48 in Sect. 21. If the KIES keyword is on, the values in

SMEP are only used for ordering the points, but they could take any value that allow the

program to sort the points in its right order.

VMEP

VMEP is a variable keyword that specifies the value of VMEP(s) at the current grid point,

in atomic units and setting the zero of energy at reactants. This keyword is required and

only accepted in the POINT sections.

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12.E. General description of file fu40 input

This file is needed only if the POTENTIAL keyword of the ENERGETICS section of file fu5 is

equal to unit40. The input from FORTRAN unit fu40 is in free format keyword style.

All input sections must start with the section name preceded by an “*”.

12.E.1 Section Descriptions

Section Name Description

*GEN40 general data such as options for input and extrapolation

*EXTRAP40 extrapolation information for the reactants and products

*R140 information for the first reactant

*R240 information for the second reactant

*P140 information for the first product

*P240 information for the second product

*WR40 information for reactant side well

*WP40 information for product side well

*SADDLE40 information for the saddle point

*POINT40 information for a point along the MEP

The POINT40 section should be repeated once for each of the points along the MEP excluding

the reactant limit, product limit, points used for extrapolation, and saddle point; i.e., POINT40

should be repeated once for each of the points s1,s2,s3,...sN (in the notation of pages 96-99

of Ref. 14 of Sect. 21) except the saddle point, and if there is a saddle point, that point should

not be specified in a POINT40 section. Each section appears at most once except POINT40,

which appears NPTS times. The sections can be in any order except that the POINT40 sections

must be in order of increasing s. The saddle point, if any, is specified in the SADDLE40

section. In reading in gradients and Hessians, the coordinates are always in this order: x, y, z

of atom 1, x, y, z of atom 2, etc.

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12.E.2 GEN40 section

Keyword Type Default Description

TITLE list blank job title or comment

PRINT variable noextra print options

MAXLPTS variable 3 maximum number of points used in Lagrange interpolation

GEOMUNIT variable bohr unit for coordinate input

GRADUNIT variable bohr unit for gradient input

FREQSOURCE variable read option for obtaining frequencies

FREQUNIT variable waven option for frequency input

HESSFORM variable full form of Hessian matrix

HESSUNIT variable bohr option for Hessian matrix input

ANHARM variable none option for anharmonicity input

CURVATURE variable setzero curvature calculation options

GRADDER variable noextra option for computing the derivative of the gradient

NPTS variable 2 number of points along the MEP at which data is to be read

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Glossary of GEN40 keywords

ANHARM

ANHARM is a variable keyword for selecting anharmonicity input.

Option Definition

none No anharmonic data is read (default).

cubic Read the third derivatives k3 with respect to the normal

coordinates at each grid point.

quartic Also read in fourth derivatives k4 with respect to the

normal

coordinates at each grid point.

Example: ANHARM cubic

CURVATURE

CURVATURE is a variable keyword used to select the way in which information about the curvature components BmF is input. For the compute option to be used,

freqsource must be set to hessian (and the Hessians must be provided in

SADDLE40 and POINT40).

Option Definition

setzero The BmF are set to zero everywhere (default).

read The BmF are read directly.

compute The BmF are computed from the gradient and Hessian as

discussed in Sections 6.H and 10.F.

Example: CURVATURE read

FREQSOURCE

FREQSOURCE is a variable keyword for selecting how the frequencies should be

determined.

Option Definition

read Frequencies are read directly (default).

hessian Frequencies are obtained by diagonalizing the Hessian or

projected Hessian matrix.

Example: FREQSOURCE hessian

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FREQUNIT

FREQUNIT is a variable keyword that specifies the units of the input frequencies.

Option Definition

waven Frequencies are given in cm-1 (default)

au Frequencies are given in atomic units.

Example: FREQUNIT au

Note: all frequencies must be input in the same units (all wavenumbers or all atomic

units), including the imaginary frequency, WSTAR.

GEOMUNIT

GEOMUNIT is a variable keyword that specifies the units of the Cartesian or mass-scaled

Cartesian coordinates. If one of the mass-scaled options is chosen, then the scaling mass

µ must be specified in unit fu5 by the variable SCALEMASS in section PATH. If µ = 1 amu

is used for scaling, then SCALEMASS does not need to be specified since 1 amu is the

default.

Option Definition

coordinates are in:

bohr unscaled bohrs (default)

msbohr mass-scaled bohrs

ang unscaled angstroms

msang mass-scaled angstroms

si unscaled meters

Example: GEOMUNIT ang

GRADDER

GRADDER is a variable keyword used to select how the derivative of the gradient is

obtained for use in calculation of the curvature components BmF. This keyword is

utilized only if CURVATURE is set to compute.

Option Definition

noextra Derivative of the gradient with respect to s is obtained from a

quadratic fit of the gradient at three points on the basic input

grid, with the middle point being the current point on the

Hessian grid (default). In the notation of Section 9.C,

noextra means that the gradient grid is the basic input grid.

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oneextra Derivative of the gradient is computed by one-sided finite

difference using the gradient on the basic input grid and a

gradient input at one extra point near the basic input grid point. oneextra means that the gradient grid has twice

as many points as the basic input grid.

twoextra Derivative of the gradient is computed from a quadratic fit

obtained using the gradient on the basic input grid and

gradients input at an extra point near and on each side of the

basic input grid point.

Example: GRADDER oneextra

GRADUNIT

GRADUNIT is a variable keyword that specifies the units of the gradients (or, if forces are

used, the unit of the force).

Option Definition

gradients are in: bohr hartrees per unscaled bohr (default)

msbohr hartrees per mass-scaled bohr

ang hartrees per unscaled Å

msang hartrees per mass-scaled Å

si joules per unscaled meter

Example: GRADUNIT msbohr

HESSFORM

HESSFORM is a variable keyword that, if hessian is specified in FREQSOURCE, specifies

the form of the Hessian matrix.

Option Definition

full F is input as the full matrix (default).

packed F is input in packed form.

Example: HESSFORM packed

If packed is selected, the lower triangular elements of F should be listed in order such

that F P i i jij = - +( ( ) )12

1 , where P(k) is element k of the input list and Fij is the

element of F in row i and column j. The number of elements listed per line is arbitrary.

Examples of both input forms for a 6 x 6 matrix is shown below:

Full matrix - example 1

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F11 F12 F13 F14 F15 F16

F21 F22 F23 F24 F25 F26

F31 F32 F33 F34 F35 F36

F41 F42 F43 F44 F45 F46

F51 F52 F53 F54 F55 F56

F61 F62 F63 F64 F65 F66

Full matrix - example 2

F11 F12 F13 F14 F15 F16 F21 F22 F23

F24 F25 F26 F31 F32 F33 F34 F35 F36

F41 F42 F43 F44 F45 F46 F51 F52 F53

F54 F55 F56 F61 F62 F63 F64 F65 F66

Packed matrix - example 1

F11

F21 F22

F31 F32 F33

F41 F42 F43 F44

F51 F52 F53 F54 F55

F61 F62 F63 F64 F65 F66

Packed matrix - example 2

F11 F21 F22 F31 F32 F33

F41 F42 F43 F44 F51 F52

F53 F54 F55 F61 F62 F63

F64 F65 F66

The order of the coordinates is explained in Section 12.E.1.

Note that GAUSSIAN94 writes the packed Hessian matrix in a slightly different way in the

standard output file, but the Hessian in the formatted checkpoint file (requested by their

FormCheck keyword) is in precisely the packed form accepted by Polyrate and so is

convenient for copying and pasting into Polyrate fu40 files.

Note that the exact F matrix is symmetric, but due to finite precision in computations, the

actual matrix one has to input is usually nonsymmetric. If one inputs a nonsymmetric full

matrix, the code uses the unsymmetric matrix. If a user wants the code to use a

symmetric matrix, we recommend taking an arithmetic average of Fij and Fji for the

resulting symmetrized elements in packed form.

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HESSUNIT

HESSUNIT is a variable keyword that, if hessian is specified in FREQSOURCE, specifies

the units of the Hessian matrix F. The choice of coordinates (mass-scaled or not) must be

consistent with GEOMUNIT.

Option Definition

Hessians are in:

bohr hartrees per unscaled bohr2 (default)

msbohr hartrees per mass-scaled bohr2

ang hartrees per unscaled Å2

msang hartrees per mass-scaled Å2

si joules per unscaled meter2

Example: HESSUNIT msbohr

Users calculating Hessians by an electronic structure package should read the manual for

that package to see what units the Hessian is in. For example, GAUSSIAN94 prints the

Hessian in hartrees per unscaled bohr2.

MAXLPTS

MAXLPTS is a variable keyword with an integer argument that specifies the maximum

number of points used in Lagrange interpolation in the procedure of Subsection 9.C. The

default value for this keyword is 3. If this keyword is set to –1, the program will

perform an IVTST-M calculation using the information read from the fu40 input file.

When using file fu40, the user cannot select any options for the IVTST-M calculation; it

will be performed according to the default options, and the number of gradient and

Hessian points have to be the same and equal to NPTS (see below). Therefore, only

IVTST-M-NPTS/NPTS calculations are allowed. The curvature components will be

interpolated using a value of 3 for the exponent in the mapping function. For

unimolecular reactions or reactions with wells, a cubic polynomial fitting to V is done previous to its spline fitting, taking a step of 0.01 a0 along the lowest frequency mode for

performing this fitting. The only way to change any of these options or to use a different

number of gradient and Hessian points is by using the fu31 input file, which is

specifically designed for IVTST-M calculations.

NPTS

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NPTS is a variable keyword with an integer argument that specifies the number of points

along the MEP (excluding the reactant limit, product limit, points used for extrapolation,

and saddle point) at which data is to be read. Unless only TST reaction rates are

calculated, file fu40 must contain a minimum of one point on each side of the saddle

point. Unless NEXTPT is on, these points must be arranged in order of increasing s. The

section POINT40 should occur NPTS times in the file 40 input. The default value for NPTS

is 2.

PRINT

PRINT is a variable keyword for selecting print options.

Option Definition

noextra Print out titles and options (default).

summary Also print out summary.

input Also echo input as it is read.

intermediate Also print out intermediate information about fitting

exponential functions and print out interpolated results each

time RPHINT is called. debugging Also print out debugging information in exponential fitting.

Example: PRINT summary

TITLE

TITLE is a list keyword that allows the user to give a one-line title to the

electronic structure file.

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12.E.3 R140, R240, P140, P240, WR40, and WP40 sections

The R140, R240, P140, P240, WR40, and WP40 sections all have the same set of keywords.

A separate section is needed for each reactant, each product, and each well.

Keyword Type Default Description

SVALUE variable dgr (or dgp) value of s (in a.u.) at the reactant (or

product)

VVALUE variable (required) potential (in a.u.) at reactant (or

product)

HESSIAN list (see Glossary) Hessian matrix for the reactant or

product species

IFREQ list 1 2 3 ... indices for reordering frequencies,

anharmonicities, and curvature

components

FREQ list (see Glossary) vibrational frequencies for the

reactant or product species

3RDDERIV list (see Glossary) third derivatives of V with respect

to motion along the normal

coordinates for the reactant or

product

4THDERIV list (see Glossary) fourth derivatives of V with respect

to motion along the normal

coordinates for the reactant or

product

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Glossary of R140, R240, P140, P240, WR40, and WP40 keywords

3RDDERIV

3RDDERIV is a list keyword that is used to specify the third derivatives of V along the

normal coordinates at the reactant, product, or well. If ANHARM is set to cubic or

quartic in the GEN40 section, this keyword is required unless the reactant or product

under consideration is monatomic.

4THDERIV

4THDERIV is a list keyword that is used to specify the fourth derivatives of V along the

normal coordinates at the reactant, product, or well. If ANHARM is set to quartic in

the GEN40 section, this keyword is required unless the reactant or product under

consideration is monatomic.

FREQ

FREQ is a list keyword that is used to specify the frequencies for each normal mode at the

reactant, product, or well species. This keyword is required if FREQSOURCE is set to

read (the default value) in the GEN40 section and is not used otherwise. The units of

the frequencies are determined by the FREQUNIT keyword in the GEN40 section.

HESSIAN

HESSIAN is a list keyword that is used to specify the Hessian matrix at the reactant, product, or well species. This keyword is required if FREQSOURCE is set to hessian in

the GEN40 section and is not used otherwise. The form and units of the Hessian matrix

are determined by the HESSFORM and HESSUNIT keywords in the GEN40 section,

respectively.

IFREQ

IFREQ is a required list keyword that is used to specify indices for reordering frequencies,

anharmonicities, and curvature components in the interpolation table in order to make the

ordering consistent with that at the saddle point and/or along the MEP. The imaginary

frequency at the saddle point is not included in this ordering. Therefore, index 1

corresponds to the largest frequency at the saddle point, index 2 corresponds to the

second largest frequency, and so on.

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SVALUE

SVALUE is a variable keyword that specifies the value of s at the reactant if the reaction is

unimolecular or at the well on the reactant side or the value of s at the product if there is

only one product or at the well on the product side. The argument of SVALUE can be

either a numerical value (in bohr), dgr (default guess for reactant or well), or dgp

(default guess for product or well). SVALUE for reactants has meaning only for a

unimolecular reaction, and SVALUE for products has meaning only for a unimolecular

rearrangement or an association reaction. SVALUE should be omitted for the reactants if

there are two or more reactants, and SVALUE should be omitted for the products if there

are two or more products. In the following definitions, sR is the value of s at the reactant

or well on the reactant side, and sP is the value of s at the product or well on the product

side.

Option Definition

(numerical value) value of sR (R140 or WR40 section) or

sP (P140 or WP40 section)

dgr sa

s s s=

-

- -

ìíî

max.

( )

2 0 0

1 2 1

dgp

VVALUE

VVALUE is a required variable keyword that specifies the value of the potential (in a.u.) at

the reactant or product.

îíì

-+=

- )(

0.2max

1

0

NNN sss

as

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12.E.4 SADDLE40 section

The SADDLE40 section is used to provide information at the saddle point, if it exists. This

section should be omitted if there is no saddle point.

Keyword Type Default Description

VVALUE variable (required) potential at saddle point

IFREQ list 1 2 3 ... indices for reordering frequencies, anharmonicities, and curvature components

HESSIAN list (see Glossary) Hessian matrix for the saddle point

FREQ list (see Glossary) vibrational frequencies for the saddle point

3RDDERIV list (see Glossary) third derivatives of V with respect to motion along the normal coordinates for the saddle point

4THDERIV list (see Glossary) fourth derivatives of V with respect to motion along the normal coordinates for the saddle point

WSTAR list (see Glossary) absolute value of the imaginary frequency at the saddle point

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Glossary of SADDLE40 keywords

3RDDERIV

3RDDERIV is a list keyword that is used to specify the third derivatives of V along the

bound normal coordinates at the saddle point. This keyword is required if ANHARM is set

to cubic or quartic in the GEN40 section.

4THDERIV

4THDERIV is a list keyword that is used to specify the fourth derivatives of V along the

bound normal coordinates at the saddle point. This keyword is required if ANHARM is set to quartic in the GEN40 section.

FREQ

FREQ is a list keyword that is used to specify the frequencies for each bound normal mode

at the saddle point. This keyword is required if FREQSOURCE is set to read (the default

value) in the GEN40 section and is not used otherwise. The units of the frequencies are

determined by the FREQUNIT keyword in the GEN40 section.

HESSIAN

HESSIAN is a list keyword that is used to specify the Hessian matrix at the saddle point.

This keyword is required if FREQSOURCE is set to hessian in the GEN40 section and is

not used otherwise. The form and units of the Hessian are determined by the HESSFORM

and HESSUNIT keywords in the GEN40 section, respectively.

IFREQ

IFREQ is a required list keyword that is used to specify indices for reordering frequencies,

anharmonicities, and curvature components in the interpolation table for the saddle point.

VVALUE

VVALUE is a required variable keyword that specifies the value of the potential (in a.u.) at

the saddle point.

WSTAR

WSTAR is a variable keyword that is used to specify the value of the imaginary frequency at the saddle point. This keyword is required if FREQSOURCE is set to read (the default

value) in the GEN40 section and is not used otherwise. The default unit for the imaginary

frequency is cm-1, but can be changed to atomic units by setting FREQUNIT to au.

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12.E.5 POINT40 section

This section should be repeated for each point along the MEP except for the reactant

limit, product limit, points used for extrapolation, and saddle point. The points must be

arranged starting from the one with the most negative s value and continuing in the

direction of increasing s.

SMEP variable (required) value of s at the current grid location along the MEP

VMEP variable (required) potential at the current grid location on the MEP

GEOM list (required) Cartesian coordinates at the current grid point

GRADS list (required) gradient vector at s along MEP

FORCES list (required) force vector at s along MEP

SB1 variable (see Glossary) value of s at a location along the MEP near the current grid point

GRADSB1 list (see Glossary) gradient vector at the extra point SB1 for computing the curvature B

FORCESB1 list (see Glossary) force vector at the extra point SB1

for computing the curvature B

SB2 variable (see Glossary) value of s at another location along the MEP near the current grid point

GRADSB2 list (see Glossary) gradient vector at the extra point SB2 for computing the curvature B

FORCESB2 list (see Glossary) force vector at the extra point SB2 for computing the curvature B

IFREQ list 1 2 3 ... indices for reordering frequencies, anharmonicities, and curvature components

Keyword Type Default Description

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HESSIAN list (see Glossary) Hessian matrix at the current grid point

FREQ list (see Glossary) vibrational frequencies at the current grid point

3RDDERIV list (see Glossary) third derivatives of V with respect to motion along the normal coordinates for the current grid point

4THDERIV list (see Glossary) fourth derivatives of V with respect to motion along the normal coordinates for the current grid point

BFS list (see Glossary) reaction path curvature components at the current grid point along the MEP

Keyword Type Default Description

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Glossary of POINT40 keywords

3RDDERIV

3RDDERIV is a list keyword that is used to specify the third derivatives of V along the

bound normal coordinates at the current grid point. This keyword is required if ANHARM

is set to cubic or quartic in the GEN40 section.

4THDERIV

4THDERIV is a list keyword that is used to specify the fourth derivatives of V along the

bound normal coordinates at the current grid point. This keyword is required if ANHARM is set to quartic in the GEN40 section.

BFS

BFS is a list keyword that is used to specify the reaction path curvature components at the

current grid point along the MEP. This keyword is required if CURVATURE is set to read

in the GEN40 section and is not used otherwise.

FORCES

FORCES is a list keyword that is used to specify the forces at the current grid point. This

keyword is required if GRADS is not used. The units of the force are determined by the

GRADUNIT keyword in the GEN40 section.

FORCESB1

FORCESB1 is a list keyword that is used to specify the force at s = SB1. This keyword is

required if GRADDER is set to oneextra or twoextra in the GEN40 section and

GRADSB1 is not used; otherwise, it is not used.

FORCESB2

FORCESB2 is a list keyword that is used to specify the force at s = SB2. This keyword is required if GRADDER is set to twoextra in the GEN40 section and GRADSB2 is not used;

otherwise, it is not used.

FREQ

FREQ is a list keyword that is used to specify the frequencies for each bound generalized

normal mode at the current grid point. This keyword is required if FREQSOURCE is set to

read (the default value) in the GEN40 section and is not used otherwise. The units of

the frequencies are determined by the FREQUNIT keyword in the GEN40 section.

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GEOM

GEOM is a list keyword that specifies the Cartesian coordinates at the current grid

location, in units determined by the GEOMUNIT keyword in the GEN40 section.

GRADS

GRADS is a list keyword that is used to specify the gradient at the current grid point. This

keyword is required if FORCES is not used. The units of the gradient are determined by

the GRADUNIT keyword in the GEN40 section.

GRADSB1

GRADSB1 is a list keyword that is used to specify the gradient at s = SB1. This keyword is

required if GRADDER is set to oneextra or twoextra in the GEN40 section and

FORCESB1 is not used; otherwise, it is not used.

GRADSB2

GRADSB2 is a list keyword that is used to specify the gradient at s = SB2. This keyword is required if GRADDER is set to twoextra in the GEN40 section and FORCESB2 is not

used; otherwise, it is not used.

HESSIAN

HESSIAN is a list keyword that is used to specify the Hessian matrix at the current grid

point. This keyword is required if FREQSOURCE is set to hessian in the GEN40 section

and is not used otherwise. The form and units of the Hessian are determined by the

HESSFORM and HESSUNIT keywords in the GEN40 section, respectively.

IFREQ

IFREQ is a list keyword that is used to specify indices for reordering frequencies,

anharmonicities, and curvature components in the interpolation table for the current grid

point.

SMEP

SMEP is a required variable keyword that specifies the value of s (in bohr) at the current

grid location along the MEP.

SB1

SB1 is a variable keyword that specifies the value of s (in bohr) at a grid location along

the MEP close to SMEP. This keyword is required if GRADDER is set to oneextra or

twoextra in the GEN40 section and is not used otherwise.

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SB2

SB2 is a variable keyword that specifies the value of s (in bohr) at a grid location along

the MEP close to SMEP, but on the opposite side of SMEP from SB1. This keyword is

required if GRADDER is set to twoextra in the GEN40 section and is not used

otherwise.

VMEP

VMEP is a required variable keyword that specifies the value of the potential at the current

grid location.

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12.F. General description of unit fu50 input

This file is only needed if the DL keyword is set to ioc in the GENERAL section of the unit

fu5 input. This allows one to calculate zero-order interpolated VTST or interpolated

optimized corrections. The input from FORTRAN unit fu50 is in free format keyword

style. In the current version of Polyrate there is only one section, VTSTIC, in the unit fu50

input file, and the first keyword in this file must be *VTSTIC. A sample unit fu50 input

file is cmcic.dat for the cmctr2 test run. A description of the input to the Polyrate code

from FORTRAN unit fu50 follows.

Keyword Type Default Description

0IVTST switch off zero-order IVTST calculation

(NO)DETMI list no correction

corrected det I

ENERXN variable required corrected exoergicity

ENESAD variable required corrected classical barrier height

(NO)FREQMAT list no matching frequency matching information

(NO)HRMI variable 99 correct the moment of inertia

FREQIMAG variable required imaginary freq. at saddle point

LOWFREQ list no correction

IVTST treatment of low freq.

MEPTYPER variable two type of reactant-side MEP

MEPTYPEP variable two type of product-side MEP

MIRP list not used corrected moments of inertia for the reactant and product

MITS list not used corrected moments of inertia for the transition state

LCTCOR variable no correction of V in the nonadiabatic region in LCT calculations

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Keyword Type Default Description

PCFREQA list not used corrected frequencies of the product-side stationary point

PCFREQS list not used lower-level frequencies of the product-side stationary point

PCINFO list not used product-side stationary point info.

SPC variable not used s value at this point

ENEPCS variable not used lower-level V at this point

ENEPCA variable not used corrected V at this point

(NO)PRODFREQ list not used corrected product frequencies

RCFREQA list not used corrected frequencies of the reactant-side stationary point

RCFREQS list not used lower-level frequencies of the reactant-side stationary point

RCINFO list not used reactant-side stationary point info.

SRC variable not used s value at this point

ENERCS variable not used lower-level V at this point

ENERCA variable not used corrected V at this point

RANGEIC list not used range parameters

RPL variable 1.0 range parameter L for an Eckart function

BR variable 5.0 range parameter for a cut-off Gaussian on the reactant side

BP variable 5.0 range parameter for a cut-off Gaussian on the product side

REACFREQ list not used corrected reactant frequencies

SADFREQ list not used corrected saddle point frequencies

UNITMI variable au units used for det I input

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Glossary for file fu50 keywords

0IVTST

0IVTST is a switch keyword that specifies that the zero-order IVTST calculation will be

performed. The default is off.

DETMI (NODETMI)

DETMI is a list keyword used to input the corrected determinant of the moment of inertia

tensor. Five values of det I (which is the determinant of the inertia tensor, also equal to

the product of the three principal moments of inertia) have to be input. They are, in the

order of input, for the first reactant species, the second reactant species, the saddle point,

the first product species, and the second product species. The units used are specified by

the UNITMI keyword, which is discussed latter in this section. For an atomic species, the

user should input a value of zero for det I. The default is NODETMI, i.e., no correction for

det I.

Example: DETMI

5.7220E16

4.9906E13

9.8871E17

5.9964E16

2.3769E13

END

ENERXN

ENERXN is a variable keyword used to input the corrected energy of the reaction in

kcal/mol, excluding zero point contributions. This is a required keyword. It should be

positive if the reaction is endoergic and negative if it is exoergic.

Example: ENERXN -5.0

ENESAD

ENESAD is a variable keyword used to input the corrected classical barrier height in

kcal/mol. This is a required keyword.

Example: ENESAD 6.0

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FREQMAT (NOFREQMAT)

FREQMAT is a list keyword used to specify the frequency matching information. The

input consists of n lines where n is the number of real saddle point frequencies. Each line

needs three numbers; the first one is the mode number of a mode at the saddle point, and

the second and the third ones are the mode numbers of the modes at the reactant-side and

product-side stationary points which match that saddle point mode. The default is

NOFREQMAT, i.e., the vibrational frequencies are automatically matched in decreasing

order. However, if the keywords MEPTYPER and MEPTYPEP, which are discussed latter in

this section, are not both equal to two, this keyword is required.

Example: FREQMAT

1 2 1

2 3 3

3 4 2

4 1 4

5 5 5

6 6 6

7 8 7

8 7 8

9 9 9

END

HRMI (NOHRMI)

HRMI is a variable keyword that specifies the correction method for the moment of inertia

of hindered-rotor modes. The default is NOHRMI. The valid arguments for the HRMI

keyword are:

Option Description

all correct the moments of inertia of all the hindered-rotor modes of

the reactants, products, and saddle point. -n(n=1,2...) same as above, and set the moments of inertia of the lowest n

GTS hindered-rotor modes for all values of s to their values at

the saddle point.

n(n=1,2...) no correction to the moment of inertia at stationary points, but set

the moments of inertia of the lowest n GTS hindered-rotor modes

for all values of s to their lower-level values at the saddle point.

Example: HRMI -1

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FREQIMAG

FREQIMAG is a variable keyword used to input the absolute value of the corrected

imaginary frequency at saddle point in cm−1. This is a required keyword.

Example: FREQIMAG 900.0

LCTCOR

LCTCOR is a variable keyword that specifies the method to correct the potential energy in

the nonadiabatic region in LCT calculations. This keyword has an effect only when LCT

calculations are performed. The default is quadlin, which provides the standard

version of the VTST-IC method as explained in Section 3.1 of Ref. 36 of Sect. 21. The

valid arguments for this keyword are:

Option Description

quadlin linear or quadratic correction depending on the magnitude of the

corrections in different regions linear linear correction only

nocor no correction

Example: LCTCOR nocor

Note: The user should take special care to make sure that this correction yields

physical results.

LOWFREQ

LOWFREQ is a list keyword used to specify that certain GTS mode frequencies are to be

interpolated using the IVTST-0 formula based on their values at three points. The

functional forms used to interpolate the specified frequencies are the same as the

IVTST-0 functions as explained in Section 4.1 of Ref. 36 of Sect. 21. Notice that this is

similar to the IVTST0FREQ keyword of the PATH section of fu5. IVTST0FREQ is used for

single-level calculations and lower levels of dual-level calculations, whereas LOWFREQ is

used for the higher level of dual-level runs. If, for a given mode, IVTST0FREQ and

LOWFREQ are both specified, then LOWFREQ overrides IVTST0FREQ.

Example: LOWFREQ

11

12

13

14

END

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MEPTYPER

MEPTYPER is a variable keyword that specifies the type of reactant-side MEP that will be

considered in the VTST-IOC calculation. The default value is two. The valid arguments

for this keyword are:

Option Description one There is only one reactant species and interpolation is carried out

between this species and the saddle point.

two There are two reactant species and interpolation is carried out

between these species (using the merged set of frequencies) and

the saddle point.

well The correction on the reactant side is based on a well.

Example: MEPTYPER one

MEPTYPEP

MEPTYPEP is a variable keyword that specifies the type of product-side MEP that will be

considered in the VTST-IOC calculation. The default is two. The valid arguments for

this keyword are:

Option Description

one There is only one product species and interpolation is carried out

between this species and the saddle point. two There are two product species and interpolation is carried out

between these species (using the merged set of frequencies) and

the saddle point.

well The correction on the product side is based on a well.

Example: MEPTYPER well

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MIRP

MIRP is a list keyword used to input the corrected moments of inertia in atomic units of

the reactant and product hindered-rotor modes. This moment of inertial is for the internal

rotation, which is not the same as the moment of inertia of the overall system. This

keyword is needed if HRMI is set to all or is less than zero. The input order is reactant

1, reactant 2 (if any), product 1, and product 2 (if any); and within each reactant and

product species the modes should be ordered from the highest frequency hindered-rotor

mode to the lowest frequency hindered-rotor mode. This keyword can be omitted if there

are no hindered-rotor modes in reactants and products.

Example: MIRP

960.50

END

MITS

MITS is a list keyword used to input the corrected moments of inertia in atomic units of

the saddle point hindered-rotor modes. The moment of inertia is for the internal rotation,

and it is not the same as the moment of inertial of the overall system. This keyword is needed if HRMI is set to all or is less than zero. The input should be ordered from the

highest frequency hindered-rotor mode to the lowest frequency hindered-rotor mode.

This keyword can be omitted if there are no hindered-rotor modes at the saddle point. In

the example below, which is for the CH4 + OH reaction, the symmetry number for the

internal rotation of the CH3 group around the C−H axis in the TS is 3:

Example: MITS

7690

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END

PCFREQA

PCFREQA is a list keyword used to input the corrected frequencies (in cm−1) of the

product-side stationary point used for the IOC correction. If the number of real frequencies is less than that of the saddle point (i.e., when MEPTYPEP is two), add zeros

after the last non-zero frequency to input a total of n frequencies, where n is the number

of real frequencies at the saddle point. There should be n + 1 input frequencies if

MEPTYPEP is not two. The order of the frequencies in the input must match the order of

the lower-level frequencies, i.e., the first frequency must correspond physically to the

highest lower-level frequency, and the second frequency must correspond physically to

the second highest lower-level frequency, and so on.

Example: PCFREQA

3124.0 2282.0 2282.0 2279.0 1489.0

1489.0 1287.0 1287.0 1111.0 1072.0

1033.0 1033.0 565.0 415.0 411.0

0.0 0.0 0.0 0.0 0.0

END

(In this example MEPTYPEP is two and there are nine atoms in the system. The first

product has four atoms and the second product has five atoms. The saddle point has

twenty real frequencies but the products have only fifteen real frequencies, so we add five

zeros at the end of input.)

PCFREQS

PCFREQS is a list keyword used to input the lower-level frequencies (in cm−1) of the product-side stationary point. This keyword is only needed when MEPTYPEP is well.

Otherwise the frequencies are just the product frequencies, and the program will have this

information when it calculates the product properties. There should be n+1 input

frequencies, where n is the number of the real frequencies at the saddle point. The

frequencies in the input must be in decreasing order.

Example: PCFREQS

3124.0 2282.0 2282.0 2279.0 1489.0

1489.0 1287.0 1287.0 1111.0 1072.0

1033.0 1033.0 565.0 415.0 411.0

END

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PCINFO

PCINFO is a list keyword used to specify the product-side stationary point information.

This keyword is needed only if MEPTYPEP is one or well. The valid subkeyword

options are defined below. There are no defaults for these subkeywords, and the user

must supply all the values, except as noted.

Option Description spc s value in bohrs at this point

enepcs lower-level potential energy in kcal/mol at this point

(required only if MEPTYPEP is well)

enepca corrected potential energy in kcal/mol at this point (required

only if MEPTYPEP is well)

nofreqcorr no frequency correction at the product complex; when this

keyword is used the keywords PCFREQA and PCFREQS are not

needed

Example: PCINFO

SPC 3.0

ENEPCS -10.0

ENEPCA -9.0

END

PRODFREQ (NOPRODFREQ)

PRODFREQ is a list keyword used to input the corrected product frequencies in cm−1. It is

only needed when MEPTYPEP is well; otherwise the corrected product frequencies are

input in the PCFREQA keyword. NOPRODFREQ specifies that no correction is needed for the product frequencies, but this is allowed only if MEPTYPEP is well. The default is to

correct the product frequencies when MEPTYPEP is well, so if NOPRODFREQ is not

specified, the PRODFREQ keyword is required. See keyword PCFREQA for the required

input order for the frequencies.

Example: PRODFREQ

3092.0 3092.0 2981.0 1453.0 1453.0

1377.0 1017.0 1017.0 741.0

END

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RCFREQA

RCFREQA is a list keyword used to input the corrected frequencies (in cm−1) of the

reactant-side stationary point that the IOC correction is based on. If the number of real

frequencies is less than that of the saddle point (i.e., when MEPTYPER is two), add zeros

after the last non-zero frequency to input a total of n frequencies, where n is the number

of real frequencies at the saddle point. There should be n+1 input frequencies if MEPTYPER is not two. The order of the frequencies in the input must match the order of

the lower-level frequencies, i.e., the first frequency must correspond physically to the

highest lower-level frequency, and the second frequency must correspond physically to

the second highest lower-level frequency, and so on.

Example (see the example for the PCFREQA keyword): RCFREQA

3124.0 2282.0 2282.0 2279.0 1489.0

1489.0 1287.0 1287.0 1111.0 1072.0

1033.0 1033.0 565.0 415.0 411.0

0.0 0.0 0.0 0.0 0.0

END

RCFREQS

RCFREQS is a list keyword used to input the flower-level frequencies (in cm−1) of the

reactant-side stationary point. This keyword is only needed when MEPTYPER is well.

Otherwise the frequencies are just the reactant frequencies, and the program will have

this information when it calculates the reactant properties. There should be n + 1 input

frequencies, where n is the number of the real frequencies at the saddle point. The

frequencies in the input must be in decreasing order.

Example: RCFREQS 3124.0 2282.0 2282.0 2279.0 1489.0

1489.0 1287.0 1287.0 1111.0 1072.0

1033.0 1033.0 565.0 415.0 411.0

END

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RCINFO

RCINFO is a list keyword used to specify the reactant-side stationary point information.

This keyword is needed only if MEPTYPER is one or well. The valid subkeyword

options are defined below. There are no defaults for these subkeywords, and the user

must supply all the values, except as noted.

Option Description src s value in bohrs at this point

enercs lower-level potential energy in kcal/mol at this point

(required only if MEPTYPER is well)

enerca corrected potential energy in kcal/mol at this point (required

only if MEPTYPER is well)

nofreqcorr no frequency correction at the reactant complex; when this

keyword is used the keywords RCFREQA and RCFREQS are not

needed

Example: RCINFO

SRC -3.0

ENERCS -5.0

ENERCA -4.0

END

RANGEIC

RANGEIC is a list keyword used to input the range parameters for the correction functions

in the VTST-IOC calculations. The valid subkeyword options are defined below.

Option Description Default

rpl range parameter L in bohrs for an Eckart function 1.0

br range parameter for a cut-off Gaussian function on 5.0

the reactant side

bp range parameter for a cut-off Gaussian function on 5.0

the product side

Example: RANGEIC

RPL 0.3

BR 10.0

BP 8.0

END

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REACFREQ

REACFREQ is a list keyword used to input the corrected reactant frequencies in cm−1. It is

required if MEPTYPER is well. Otherwise the reactant frequencies are input in RCFREQA

keyword. See keyword RCFREQA for the requirement on the input order of the

frequencies.

Example: REACFREQ

3092.0 3092.0 2981.0 1453.0 1453.0

1377.0 1017.0 1017.0 741.0

END

SADFREQ

SADFREQ is a list keyword used to input the corrected real saddle point frequencies in

cm−1. It is a required keyword. See keyword RCFREQA for the required input order for

the frequencies.

Example: SADFREQ

3748.0 3130.0 3259.0 3255.0 1414.0

1521.0 1494.0 1298.0 1206.0 933.0

769.0 357.0 316.0 40.0

END

UNITMI

UNITMI is a variable keyword that specifies the units used for the DETMI keyword input. The default is au. The valid arguments are:

Option Description

au atomic units

si SI units, i.e., kg m2 or (kg m2)3

cgs c.g.s. units, i.e., g cm2 or (g cm2)3

scale scaled units, i.e., 10−40 g cm2 or (10−40 g cm2)3

amu atomic mass unit, i.e., a.m.u. bohr2 or (a.m.u. bohr2)3 .

Example: UNITMI AMU

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12.G. General description of unit fu51 input

This file is only needed if the ispe option is specified with the DL keyword in the

GENERAL section of unit fu5. The single-point energy correction (VTST-ISPE) is used to

correct the energies along the reaction path. The input from FORTRAN unit fu51 is in

free format keyword style. A description of the input to the Polyrate code from

FORTRAN unit fu51 follows.

12.G.1. Section Descriptions

Section Name Description

*ISPEGEN general section for stationary point information

*POINT section for the extra points along the reaction path

The *POINT section should be repeated once for each of the points along the reaction path

excluding the reactants, products, saddle point, and wells.

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12.G.2 ISPEGEN section

The *ISPEGEN section is used to provide information at the stationary points.

Keyword Type Default Description

EXERXN variable required corrected exoergicity

ENESAD variable required corrected classical barrier height

MEPTYPER variable two type of reactant-side MEP

MEPTYPEP variable two type of product-side MEP

PCINFO list not used product-side stationary point data

SPC variable not used value of s at this point

ENEPCS variable not used lower-level V at this point

ENEPCA variable not used corrected V at this point

RCINFO list not used reactant-side stationary point data

SRC variable not used value of s at this point

ENERCS variable not used lower-level V at this point

ENERCA variable not used corrected V at this point

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Glossary of ISPEGEN keywords

EXERXN

EXERXN is a variable keyword used to input the corrected classical energy change of the

reaction in kcal/mol, excluding zero-point contributions. This is a required keyword. It

should be positive if the reaction is endoergic and negative if it is exoergic. In other

words, this is the corrected product energy relative to the reactant energy.

Example: EXERXN -5.0

ENESAD

ENESAD is a variable keyword used to input the corrected classical barrier height in

kcal/mol. This is a required keyword.

Example: ENESAD 6.0

MEPTYPEP

MEPTYPEP is a variable keyword that specifies the type of product-side MEP that will be

considered in the VTST-ISPE calculation. The default is two. The valid arguments for

this keyword are:

Option Description

one There is one product and wells, if any, are not

recognized. two There are two products and wells, if any, are not

recognized.

well A product well is recognized.

Example: MEPTYPEP one

MEPTYPER

MEPTYPER is a variable keyword that specifies the type of reactant-side MEP that will be considered in the VTST-ISPE calculation. The default is two. The valid arguments for

this keyword are:

Option Description

one There is one reactant and wells, if any, are not recognized.

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two There are two reactants and wells, if any, are not

recognized. well A reactant well is recognized.

Example: MEPTYPER one

PCINFO

PCINFO is a list keyword used to specify the product-side stationary point information.

This keyword is needed only if MEPTYPEP is set to one or well. There are no defaults

for these options, the user must supply all values except as otherwise noted. The valid

options for this keyword are:

Option Description spc value of s, in bohrs, at this point

enepcs lower-level potential energy, in kcal/mol, at this point with

respect to the reactant (required if and only if MEPTYPEP is

set to well)

enepca corrected potential energy, in kcal/mol, at this point with

respect to the reactant (required if and only if MEPTYPEP is

set to well)

Example:

PCINFO spc 3.0

enepcs -10.0

enepca -9.0

RCINFO

RCINFO is a list keyword used to specify the reactant-side stationary point information.

This keyword is needed only if MEPTYPER is set to one or well. There are no defaults

for these options, the user must supply all values except as otherwise noted. The val id

options for this keyword are:

Option Description src value of s, in bohrs, at this point

enercs lower-level potential energy, in kcal/mol, at this point with

respect to the reactant (required if and only if MEPTYPER is

set to well)

enerca corrected potential energy, in kcal/mol, at this point with

respect to the reactant (required if and only if MEPTYPER is

set to well)

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Example:

PCINFO src -3.0

enercs -5.0

enerca -4.0

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12.G.3 POINT section

The POINT section should be repeated for each point along the MEP, except for the

reactants, products, saddle point, and wells. Each new POINT section must begin with

*POINT. The points can be arranged in any order.

Keyword Type Default Description

DVMEP variable variable difference in the corrected energy at point

SMEP variable required value of s at point

VMEP variable variable corrected energy at point

Notice that in the POINT section, the keyword SMEP is required and either VMEP or

DVMEP is needed for indicating the energy at a higher-level or difference of the energy at

a higher-level to the lower-level one.

Glossary of POINT keywords

DVMEP

DVMEP is a variable keyword that can be used to specify the energy difference between

the higher-level along the MEP from the lower-level ones. Using the VMEP keyword to

indicate the higher-level potential energies along the lower-level MEP has a limitation,

namely that the point chosen has to be a save-grid point of the lower-level path.

However, using the DVMEP keyword, the point chosen does not have to be a save-grid

point of the lower-level path because the difference in potential energies from the higher-

level to the lower-level is read instead of calculated.

Example: VMEP 5.1608

SMEP

SMEP is a variable keyword that specifies the value of s, in bohrs, at the current point

along the MEP.

Example: SMEP -0.8

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VMEP

VMEP is a variable keyword that specifies the energy at the current point along the MEP.

Example: VMEP 10.5

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13. DESCRIPTION OF INPUT FOR VRC-VTST

In VRC-VTST rate calculations, input file fu5 is the only one required; the other input

files used in RP-VTST calculations are not needed.

13.A Section descriptions of input file fu5

The following input sections correspond to the major parts of a VRC-VTST rate

calculation. Each section begins with a line giving the section name, preceded by an “*”.

Keywords for each section are discussed further in the rest of this subsection. In each

section, we list the keywords used in VRC-VTST rate calculations. The keywords that

are only used for VRC-VTST are discussed in this section; the keywords that can be used

for both RP-VTST and VRC-VTST are not discussed again and users can find the details

in Section 12.

Section Name Description

*GENERAL general data such as the title and defining the atoms involved

*ENERGETICS options for computing potential energy

*REACT1 definition and properties of the first reactant

*REACT2 definition and properties of the second reactant

*START Only used to define the electronic degeneracy for generalized

transition state

*PROD1 definition and properties of the first product

*PATH definition of reaction coordinate range and step size

*RATE options for computing the reaction rate

13.A.1. GENERAL section

The table below lists all the valid keywords for the GENERAL section. Indented keywords

are level-2 keywords, and the others are level-1 keywords. Level-2 keywords are always

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associated with a level-1 list keyword and must come after that keyword and before any

other level-1 keyword or starred header. In the alphabetical glossary that follows the box

that are only used for VRC-VTST rate calculations. In any run for VRC-VTST this

section would have the TITLE, ATOMS, and VRC keywords.

Basic:

Keyword Type Default Description

TITLE list blank title with 5 lines maximum

ATOMS list required atoms in system

CHECK switch off check the input data

INPUNIT variable angstrom specifies the units in fu5 input file

OUTUNIT variable angstrom specifies the units in fu6 and fu14 output files

SUPERMOL switch on supermolecule mode for reactants and products

VRC switch Off use variable reaction coordinate to treat association reaction with loose transition state

VRCOPT list not used variable reaction coordinate algorithm options

JMAX variable 300 maximum angular momentum quantum number J in E,J -VT

JSTEP variable 5 step size in the integral over J in E,J -VT

GTYPE variable 4 type of random number generator in SPRNG

NITER variable 4 Gauss-Laguerre quadrature

NMC variable 1000 number of Monte Carlo samples per facet in multifaceted dividing surface

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Glossary of GENERAL keywords only used for VRC-VTST

VRC

VRC is a switch keyword that allows the user to employ the variable reaction coordinate

algorithm to treat loose transition states. When this keyword is turned on, the PROD1,

PROD2, WELLR, WELLP, and START sections are not used in fu5 input file. Only forward

reaction rates will be calculated in this case. If each reactant has only one pivot point, a

spherical (i.e. single-faceted) dividing surface will be used. If more than one pivot point

is assigned to one or two of the reactants, a multifaceted dividing surface will be used.

Any keywords related the MEP algorithm are not used when VRC is turned on.

VRCOPT

VRCOPT is a list keyword that allows the user control over the parameters used in

variable reaction coordinate algorithm. If VRCOPT is given then it is assumed that the VRC

calculation is desired and the default for VRC becomes on. The valid options are defined

below.

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Option Description Default

jmax maximum angular momentum quantum number J 300

calculated for the number of accessible state N(E,J ) in

E,J -VT

jstep step size of angular momentum quantum number J in the 5

integral over J to calculate the contribution to reactive

flux from transitional modes

gtype the type of random number generator in SPRNG package. 4

Type 4 is Multiplicative Lagged Fibonacci Generator in

SPRNG version 2.0. It is not recommended to change the

default value. User needs to refer SPRNG manual to

change the value to the desired type. niter number of Gauss-Laguerre quadrature points for total 4

energy E.

nmc number of Monte Carlo sampling for each facet in a 1000

multifaceted dividing surface. In parallel calculation, the

actual number used in the calculation may be changed

according to the number of processors used. If the

remainder when NMC is divided by number of processors

is not zero or NMC is smaller than number of processors,

the number of sampling for each processor will be

int(NMC/number of processors) + 1. User need to be

careful to balance the nmc and number of processors

used in parallel calculation.

Example: VRCOPT

NMC 600

JMAX 500

JSTEP 10

END

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13.A.2. ENERGETICS section

The ENERGETICS section is used to define the method for computing the potential energy

of the reacting system. The table below lists all the valid keywords for the ENERGETICS

section. In the alphabetical glossary a more complete explanation for each keyword is

given.

Keyword Type Default Description

EZERO variable calculate method for determining zero of E

EZUNIT variable a.u. units of zero of energy

POTENTIAL variable hooks type of PES to be used

Glossary of ENERGETICS keywords

EZERO

Refer to Section 12.A.3

EZUNIT

Refer to Section 12.A.3

POTENTIAL

POTENTIAL is a variable keyword that allows the user to specify the source of the potential

energy information for a single-level calculation. There are only one valid option for a

VRC-VTST calculation, namely hooks. The option hooks means that the user is

providing potential information through the hooks. When Polyrate is used as a stand-

alone package, the hooks call SURF and SETUP; this is how one supplies an analytic

potential energy surface. When Polyrate is used in conjunction with a interface program,

e.g. GAUSSRATE, the hooks call the corresponding electronic structure program to

perform electronic structure calculations to obtained potential energy.

Option Definition

hooks use the hooks

Example: POTENTIAL hooks

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13.A.3. OPTIMIZATION section

The OPTIMIZATION section is used to specify the method for carrying out geometry

optimizations when the POTENTIAL keyword selection is hooks. In principle, the

keywords used for RP-VTST can also be used for VRC-VTST to optimize reactants. But

these keywords have not been tested for VRC-VTST calculations. Therefore it is strongly

recommended to input the optimized geometries instead of using Polyrate to optimize the

reactant geometries because a semi-global analytical potential energy surface when using

Polyrate as a stand-alone package is required in VRC-VTST calculation and it usually

doesn’t have analytical derivatives used for geometry optimization.

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13.A.4. REACT1, REACT2, PROD1, AND START sections

The summary table below gives the keywords that can be used for a VRC-VTST

calculations in REACT1, REACT2, PROD1, and START sections. Note that in VRC-VTST

calculations an additional keyword is introduced for setting the Cartesian coordinates of

pivot points used for the variable reaction coordinate. These pivot points are only

required in the REACT1 and REACT2 sections.

In START section, only the ELEC keyword is used. This gives electronic degeneracy of

the generalized transition state. No other keyword is required in this section when

Polyrate runs as a stand-alone program. When running in direct dynamics with other rate

program, e.g. GAUSSRATE, the STATUS keyword should be set to 6 to avoid any electronic

structure calculation for START section.

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Basic:

Keyword Type Default Description

Required:

GEOM list required Cartesian coordinates of atoms

PIVOT list Required only

for reactants

Cartesian coordinates of pivot

points for reactants

Common:

ELEC list

all degen. = 1 electronic degeneracies

ENERGY variable none energy of the stationary point

FREQ switch on perform normal-mode analysis

FREQUNIT variable waven units of the frequencies

INITGEO variable geom location of input data that specify initial geometries

STATUS variable 0 status of the stationary point work

SPECIES variable nonlinrp species type (linearity)

VIB list none

frequencies of the stationary

points

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Glossary of REACT1 and REACT2 keywords

PIVOT

PIVOT is a list keyword that is used to define the locations of pivot points. The Cartesian

coordinates of pivot points must be given along with their identification number. The

identification number can be the same for pivot points on the different reactants. The

origin of the Cartesian coordinates must be the same as the origin of the corresponding

reactant Cartesian coordinates, so that they can give the positions relative to the

corresponding reactant.

Example: PIVOT

1 0.000000 0.000000 0.200000

2 0.000000 0.000000 -0.200000

END

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13.A.5. PATH section

The PATH section contains the keywords that control the calculation of the reaction path.

In VRC-VTST rate calculations, only one keyword, SVRC, is allowed in this section.

SVRC

SVRC is a list keyword that specifies the reaction coordinate s range and step size used in

variable reaction coordinate and single-faceted or multifaceted dividing surface algorithm

for loose transition state. If VRC keyword in GENERAL section is turned on, user needs to

specify this keyword only in the PATH section, and the other keywords in the PATH

section are not required.

Example: SVRC

2.0 4.0 0.1

END

This example tells the program that the s range is 2.0 – 4.0 Å (note that default unit is Å)

and that the step size is 0.1 Å.

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13.A.6. RATE section

The RATE section contains the keywords that control the rate constant calculations. Note

that a conventional TST calculation is not a valid option for VRC-VTST rate since there is

no barrier on potential energy surface. Only forward rate constants (bimolecular

association rate) are calculated for VRC-VTS and the reverse unimolecular dissociation

rate calculation is not implemented yet. The VRC-VTST rate constants are calculated by

CVT, VT, and E,J -VT. An alphabetical glossary of all the keywords follows the

summary table.

Keyword Type Default Description

SIGMAF variable 1.0 sym. factor for forward reaction

SIGMAR Variable 1.0 sym. Factor for reversed reaction

TEMP list see below temperatures for rate calculations

SIGMAF

SIGMAF is a variable keyword whose argument specifies the number of equivalent ways

for forming the GTS for the forward reaction. Note that only two values are used in

VRC-VTST calculations. The value should be 1 for the case where the two reactants are

different, and the value should be 0.5 for the case two reactants are identical.

SIGMAR

SIGMAF is a variable keyword whose argument specifies the number of equivalent ways

for forming the GTS for the reversed reaction.

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14. GENERAL DESCRIPTION OF LCT FILES

In the calculation of LCT probabilities, relevant quantities such as theta integrals (i.e.,

imaginary action integrals) are evaluated on the grid defined by the input parameters

NQTH and NGTHETA. The stored information is then used for interpolation. When extra

output of the LCT calculations is chosen (LCTDETAIL keyword), the details of the

calculation of these quantities at certain grid points, which are specified by user, are

given in files poly.fu41 through poly.fu47. The contents of each output file are listed in

the table below. In the table, 'each tunneling path' refers to a tunneling path

corresponding to an energy quadrature point, IE, that is within the range specified in the

keyword LCTDETAIL in the TUNNEL section of unit fu5 input.

File name Fortran

Unit Contents

poly.fu41 fu41 the theta integrand and the weighting factor at each point

on each tunneling path, within its adiabatic region.

poly.fu42 fu42 the theta integrand, the effective potential, the classical

potential, and the potential correction terms, for each

point on each tunneling path, in its non-adiabatic region

poly.fu43 fu43 the theta integrals and the boundaries of the nonadiabatic

region of each tunneling path

poly.fu44 fu44 the length of the tunneling path

poly.fu45 fu45 the corresponding s value on the MEP for each point on

each tunneling path

poly.fu46 fu46 the adiabatic potential and the cosine of the angle

between the tunneling path and the gradient vector of the

MEP at the s value to which the point on the tunneling

path corresponds for each point on each tunneling path

poly.fu47 fu47 the vibrational turning points, the projection onto each

normal mode coordinate, and the curvature components

for each point on each tunneling path

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Part V More General Program Package Information

15. INSTALLING AND USING POLYRATE

A step-by-step procedure for installing, testing, and using Polyrate is given in this

section. The file structure and the Perl and C Shell scripts should make Polyrate

reasonably easy to install, test, and use.

Subsection 15.A discusses running Polyrate in a Unix environment, including Linux.

Subsection 15.B contains information for users who do not wish to use the provided Unix

scripts or who wish to run Polyrate in a non-Unix environment.

15.A. Instructions for a Unix environment

If the Polyrate program has been received in tar.gz format, the recommended directory

structure will be created automatically when this file is uncompressed and untarred, and

the files will be put in their canonical places as listed in Subsection 15.A.1.

15.A.1. Installation

Before you start, make sure all the file names are in lower case. For the purpose of

illustration, we use upper case for sample directory names, e.g., PDIR. Here PDIR is the

directory above the Polyrate17 directory, i.e., it is the parent directory where you are

going to install POLYRATE.

Polyrate may be downloaded as a single tar.gz file with a structure that is illustrated in

STEP 1. To uncompress and untar the Polyrate tar.gz file in the canonical place the user

has to execute: user@machine [~/Polyrate17] % tar –xzvf Polyrate17.tar.gz

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STEP 1 Verify that the following directory structure was created properly when the file

was uncompressed and untarred. User may use the ‘ls –R’ command.

user@machine [~/Polyrate17] % ls –R

PC/ doc/ obj/ script/ src/ sprng2.0/ testrun/ configure* exe/ poten/ set_machine.jc* testo/ util/ ./PC: check_test.pl poly_ch4cl/ poly_ch5/ poly_cwmc/ poly_hni/ poly_oh3/ clean_test.bat poly_ch4o/ poly_clhbr/ poly_h2ni/ poly_ho2/ poly_ohcl/ clean_update.bat poly_ch4oh/ poly_cmc/ poly_h3/ poly_nh3/ run_all.bat

./PC/poly_ch4cl: poly_ch4cl.mak poly_ch4cl.mdp run_ch4cl.bat ./PC/poly_ch4o: poly_ch4o.mak poly_ch4o.mdp run_ch4o.bat

./PC/poly_ch4oh: run_ch4oh.bat ./PC/poly_ch5: poly_ch5.mak poly_ch5.mdp run_ch5.bat run_lola.bat run_lola.bat.bak

./PC/poly_clhbr: poly_clhbr.mak poly_clhbr.mdp run_clhbr.bat ./PC/poly_cmc: poly_cmc.mak poly_cmc.mdp run_cmc.bat

./PC/poly_cwmc: poly_cwmc.mak poly_cwmc.mdp run_cwmc.bat ./PC/poly_h2ni: poly_h2ni.mak poly_h2ni.mdp run_h2ni.bat

./PC/poly_h3: poly_h3.mak poly_h3.mdp run_h3.bat ./PC/poly_hni: hnitr1.dat hnitr1.fu15 hnitr1.fu6 poly_hni.mak pothni.dat

hnitr1.fu14 hnitr1.fu5 hnitr1.fu61 poly_hni.mdp run_hni.bat ./PC/poly_ho2: poly_ho2.mak poly_ho2.mdp run_ho2.bat ./PC/poly_nh3:

poly_nh3.mak poly_nh3.mdp run_nh3.bat ./PC/poly_oh3: poly_oh3.mak poly_oh3.mdp run_oh3.bat ./PC/poly_ohcl:

poly_ohcl.mak poly_ohcl.mdp run_ohcl.bat

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./doc: ./exe:

./obj: ./poten: c2h7pot5.f ch4o_module.f90 chain4.F coord3.F dumpot.F h3.F ho2.F ohcl.F potch5j2.dat potcwmc3b.dat poth2nilat.dat setup4.F ch3.F ch5.F clhbr.F coord4.F h2ni.F h3_module.F nh3.F potch4o.dat potcmc1.dat potcwmcvib.dat pothni.dat surf3.F

ch4o.F chain3.F cmc.F cwmc.F h2o2.F hni.F oh3.F potch5j1.dat potcmc2.dat poth2niads.dat setup3.F surf4.F ./script: comp_pot.jc* comp_src.jc* exe_chk.jc* link_exe.jc* potcomp.jc*

./src: aamod.f90 dattim.F ef.F fromlapack.F hooks.F intbsv2.F.bak ivtstm.F Makefile polyag.F polymq.F rtpjac.F util.f90 acespoly.F dummy_mpi.F energetics.F givtst.F intbsv1.F intbsv3.F main.F poly31.F polyhl.F polyrr.F sprng_f.h vrctst_mpi.F alloc.f90 dumpot.F fromblas.F headr.F intbsv2.F interface.F main_vrcmpi.F poly40.F poly_mpi.F polysz.F torsion.f90

./src/acesrate: acespoly.F ./src/morate: mopoly.F

./testo: ch3tr1.fu15 ch5fu40tr2.fu15 ch5j1tr2.fu15 cmctr1.fu15 nh3tr1.fu6 oh3tr2.fu15 ch4cltr1.fu15 ch5fu40tr3.fu15 ch5j1tr3.fu15 cmctr2.fu15 nh3tr2.fu15 oh3tr3.fu15 ch4cltr2.fu15 ch5fu40tr4.fu15 ch5j1tr4.fu15 cmctr3.fu15 oh3fu30tr1.fu15 oh3tr4.fu15 ch4ohtr1.fu15 ch5fu40tr5.fu15 ch5j1tr5.fu15 cwmctr1.fu15 oh3fu30tr2.fu15 oh3tr5.fu15

ch4ohtr2.fu15 ch5fu40tr6.fu15 ch5j1tr6.fu15 cwmctr2.fu15 oh3fu30tr3.fu15 oh3tr6.fu15 ch4ohtr3.fu15 ch5fu50tr1.fu15 ch5j1tr7.fu15 cwmctr3.fu15 oh3fu30tr4.fu6 oh3tr7.fu15 ch4ohtr4.fu15 ch5fu50tr2.fu15 ch5j1tr8.fu15 h2nitr1.fu15 oh3fu30tr5.fu6 oh3tr8.fu15 ch4otr1.fu15 ch5fu50tr3.fu15 ch5j1tr9.fu15 h3o2fu31tr1.fu15 oh3fu30tr6.fu15 oh3tr9.fu15 ch5fu29tr1.fu15 ch5fu51tr1.fu15 ch5j2itr1.fu15 h3tr1.fu15 oh3fu31tr1.fu15 ohcltr1.fu15 ch5fu29tr2.fu15 ch5icfu30tr1.fu15 ch5j2itr2.fu15 h3tr2.fu15 oh3fu31tr2.fu15 ohcltr2.fu15

ch5fu30tr1.fu15 ch5icfu30tr2.fu15 ch5j2tr1.fu15 h3tr3.fu15 oh3fu40tr1.fu15 ohcltr3.fu15 ch5fu30tr2.fu15 ch5icfu31tr1.fu15 ch5j2tr2.fu6 h3tr4.fu15 oh3fu40tr2.fu15 ohcltr4.fu15 ch5fu30tr3.fu15 ch5icfu40tr1.fu15 ch5j2tr3.fu15 hnitr1.fu15 oh3fu40tr3.fu15 ohcltr5.fu15 ch5fu30tr4.fu15 ch5icfu40tr2.fu15 clhbrtr1.fu15 ho2tr1.fu15 oh3fu40tr4.fu6 ch5fu30tr5.fu15 ch5j1tr10.fu15 clhbrtr2.fu15 ho2tr2.fu15 oh3fu40tr5.fu6 ch5fu30tr6.fu15 ch5j1tr11.fu15 clhbrtr3.fu15 ho2tr3.fu15 oh3fu40tr6.fu15

ch5fu31tr1.fu15 ch5j1tr12.fu15 clhbrtr4.fu15 ho2tr4.fu15 oh3tr10.fu15 ch5fu40tr1.fu15 ch5j1tr1.fu15 clhbrtr5.fu15 ho2tr5.fu15 oh3tr1.fu15 ./testrun: ch3 ch5 clhbr nh3 runch3.jc runch5.jc runh2ni.jc runho2.jc ch4cl check_all.jc cmc h3 h3o2 oh3 runch4cl.jc runclhbr.jc runh3o2.jc runnh3.jc

ch4o check_test.jc cwmc hni ohcl runch4oh.jc runcmc.jc runh3.jc runoh3.jc ch4oh clean_up.jc h2ni ho2 run_all.jc runch4o.jc runcwmc.jc runhni.jc runohcl.jc ./testrun/ch3:

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ch3tr1.dat ch3tr1.jc ./testrun/ch4cl: ch4cltr1.dat ch4cltr1.fu29 ch4cltr1.jc* ch4cltr2.dat ch4cltr2.fu29 ch4cltr2.jc*

./testrun/ch4o: ch4otr1.dat ch4otr1.jc* ./testrun/ch4oh: ch4ohic.dat ch4ohiv.dat ch4ohiv2.dat ch4ohtr1.dat ch4ohtr1.jc* ch4ohtr2.dat ch4ohtr2.fu29

ch4ohtr2.jc* ./testrun/ch5: ch5fu29tr1.dat ch5fu30tr5.fu30 ch5fu40tr4.jc* ch5icfu30tr1.dat ch5icfu40tr2.jc* ch5j1tr7.dat ch5fu29tr1.fu29 ch5fu30tr5.jc* ch5fu40tr5.dat ch5icfu30tr1.fu30 ch5j1tr1.dat ch5j1tr7.jc* ch5fu29tr1.jc* ch5fu30tr6.dat ch5fu40tr5.fu40 ch5icfu30tr1.fu50 ch5j1tr1.jc* ch5j1tr8.dat

ch5fu29tr2.dat ch5fu30tr6.fu30 ch5fu40tr5.jc* ch5icfu30tr1.jc* ch5j1tr10.dat ch5j1tr8.jc* ch5fu29tr2.fu29 ch5fu30tr6.jc* ch5fu40tr6.dat ch5icfu30tr2.dat ch5j1tr10.jc* ch5j1tr9.dat ch5fu29tr2.jc* ch5fu31tr1.dat ch5fu40tr6.fu40 ch5icfu30tr2.fu30 ch5j1tr11.dat ch5j1tr9.jc* ch5fu30tr1.dat ch5fu31tr1.fu31 ch5fu40tr6.jc* ch5icfu30tr2.fu50 ch5j1tr11.jc* ch5j2itr1.dat ch5fu30tr1.fu30 ch5fu31tr1.jc* ch5fu50tr1.dat ch5icfu30tr2.jc* ch5j1tr12.dat ch5j2itr1.fu29 ch5fu30tr1.jc* ch5fu40tr1.dat ch5fu50tr1.fu50 ch5icfu31tr1.dat ch5j1tr12.jc* ch5j2itr1.jc*

ch5fu30tr2.dat ch5fu40tr1.fu40 ch5fu50tr1.jc* ch5icfu31tr1.fu31 ch5j1tr2.dat ch5j2itr2.dat ch5fu30tr2.fu30 ch5fu40tr1.jc* ch5fu50tr2.dat ch5icfu31tr1.fu50 ch5j1tr2.jc* ch5j2itr2.fu29 ch5fu30tr2.jc* ch5fu40tr2.dat ch5fu50tr2.fu50 ch5icfu31tr1.jc* ch5j1tr3.dat ch5j2itr2.jc* ch5fu30tr3.dat ch5fu40tr2.fu40 ch5fu50tr2.jc* ch5icfu40tr1.dat ch5j1tr3.jc* ch5j2tr1.dat ch5fu30tr3.fu30 ch5fu40tr2.jc* ch5fu50tr3.dat ch5icfu40tr1.fu40 ch5j1tr4.dat ch5j2tr1.jc* ch5fu30tr3.jc* ch5fu40tr3.dat ch5fu50tr3.fu50 ch5icfu40tr1.fu50 ch5j1tr4.jc* ch5j2tr2.dat

ch5fu30tr4.dat ch5fu40tr3.fu40 ch5fu50tr3.jc* ch5icfu40tr1.jc* ch5j1tr5.dat ch5j2tr2.jc* ch5fu30tr4.fu30 ch5fu40tr3.jc* ch5fu51tr1.dat ch5icfu40tr2.dat ch5j1tr5.jc* ch5j2tr3.dat ch5fu30tr4.jc* ch5fu40tr4.dat ch5fu51tr1.fu51 ch5icfu40tr2.fu40 ch5j1tr6.dat ch5j2tr3.jc* ch5fu30tr5.dat ch5fu40tr4.fu40 ch5fu51tr1.jc* ch5icfu40tr2.fu50 ch5j1tr6.jc* ./testrun/clhbr:

clhbrtr1.dat clhbrtr2.dat clhbrtr3.dat clhbrtr4.dat clhbrtr5.dat clhbrtr1.jc* clhbrtr2.jc* clhbrtr3.jc* clhbrtr4.jc* clhbrtr5.jc* ./testrun/cmc: cmcic.dat cmctr1.dat cmctr1.jc* cmctr2.dat cmctr2.jc* cmctr3.dat cmctr3.fu51 cmctr3.jc*

./testrun/cwmc: cwmctr1.dat cwmctr1.jc* cwmctr2.dat cwmctr2.jc* cwmctr3.dat cwmctr3.jc* ./testrun/h2ni: h2nitr1.dat h2nitr1.jc*

./testrun/h3o2: h3o2fu31tr1.dat h3o2fu31tr1.jc h3o2fu31tr1.fu31 ./testrun/h3: h3tr1.dat h3tr1.jc* h3tr2.dat h3tr2.jc* h3tr3.dat h3tr3.jc* h3tr4.dat h3tr4.jc*

./testrun/hni: hnitr1.dat hnitr1.jc* ./testrun/ho2:

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ho2ic.dat ho2tr1.jc* ho2tr2.jc* ho2tr4.dat ho2tr5.dat ho2tr1.dat ho2tr2.dat ho2tr3.dat ho2tr3.jc* ho2tr4.jc* ho2tr5.jc* ./testrun/nh3:

nh3ic.dat nh3tr1.dat nh3tr1.jc* nh3tr2.dat nh3tr2.jc*

./testrun/oh3: oh3fu30tr1.dat oh3fu30tr4.dat oh3fu30tr7.dat oh3fu40tr1.dat oh3fu40tr4.dat oh3tr1.dat oh3tr3.jc* oh3tr8.dat oh3fu30tr1.fu30 oh3fu30tr4.fu30 oh3fu30tr7.fu30 oh3fu40tr1.fu40 oh3fu40tr4.fu40 oh3tr1.jc* oh3tr4.dat oh3tr8.jc*

oh3fu30tr1.jc* oh3fu30tr4.jc* oh3fu30tr7.jc* oh3fu40tr1.jc* oh3fu40tr4.jc* oh3tr10.dat oh3tr4.jc* oh3tr9.dat oh3fu30tr2.dat oh3fu30tr5.dat oh3fu31tr1.dat oh3fu40tr2.dat oh3fu40tr5.dat oh3tr10.jc* oh3tr5.dat oh3tr9.jc* oh3fu30tr2.fu30 oh3fu30tr5.fu30 oh3fu31tr1.fu31 oh3fu40tr2.fu40 oh3fu40tr5.fu40 oh3tr11.dat oh3tr5.jc* tr7old.fu30

oh3fu30tr2.jc* oh3fu30tr5.jc* oh3fu31tr1.jc* oh3fu40tr2.jc* oh3fu40tr5.jc* oh3tr11.jc* oh3tr6.dat oh3fu30tr3.dat oh3fu30tr6.dat oh3fu31tr2.dat oh3fu40tr3.dat oh3fu40tr6.dat oh3tr2.dat oh3tr6.jc* oh3fu30tr3.fu30 oh3fu30tr6.fu30 oh3fu31tr2.fu31 oh3fu40tr3.fu40 oh3fu40tr6.fu40 oh3tr2.jc* oh3tr7.dat

oh3fu30tr3.jc* oh3fu30tr6.jc* oh3fu31tr2.jc* oh3fu40tr3.jc* oh3fu40tr6.jc* oh3tr3.dat oh3tr7.jc* ./testrun/ohcl: ohcltr1.dat ohcltr1.jc* ohcltr2.dat ohcltr2.jc* ohcltr3.dat ohcltr3.jc* ohcltr4.dat ohcltr4.jc*

./util: ch4.mi dattim.altix dattim.f dattim.ibm detmi.doc findl.f reord30.f ch4oh.mi dattim.compaq dattim.f90 dattim.iris detmi.f hrotor.doc rotate/ cwmc.rmi dattim.cray dattim.gnu dattim.linux detmi.jc* hrotor.f dateclock.c dattim.dec dattim.hp dattim.sun findb.f oh.mi

./util/rotate: rotate.doc rotate30/ rotate31/ rotate40/ ./util/rotate/rotate30: rotate30.f rotate30.jc* test30.dat test30.fu30

./util/rotate/rotate31: rotate31.f rotate31.jc* test31.dat test31.fu31 ./util/rotate/rotate40: rotate40.f rotate40.jc* test40.dat test40.fu40

STEP 2 Change your working directory to the Polyrate17 directory and run the script

configure by typing ./configure <Return>. You will be asked if you want this

version to be your default version of POLYRATE. If you select yes, then the

hidden files .poly_path and .poly_ver will point to the location and the version

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of POLYRATE, respectively that you are installing. Then the script will ask

which kind of executable (RP-VTST or VRC-VTST) the Makefile to generate.

You should input your choice, i.e., “RP” or “VRC”. Next, the script will

automatically detect available C and FORTRAN compilers and ask if you want to

use the detected options. Usually, you should answer “yes” so that you can use

the automatically detected compilers. If you want to use a different compiler,

you should do the followings: (step 1) answer “yes” and proceed with the

current configuring; (step 2) go to src/ directory, and open the Makefile; (step

3) At the beginning of the Makefile, you will see:

F77C = /usr/bin/gfortran -O -fno-automatic

CC = /usr/bin/gcc

Please change the definition of these two variables (F77C and CC) to the

location of your fortran and C compilers.

Note that no executable file is generated in this configuration step and the

generated Makefile is for either RP-VTST or VRC-VTST.

STEP 3 Check the Makefile to ensure that the correct compiler options appear.

POLYRATE17 supports dynamic memory but previous versions do not, so

compiler options that force static memory are typically required for previous

versions. For example, the g77 compiler requires the flag ‘-fno-automatic’,

and the Portland Group compiler requires the flag ‘-Msave’. Due to the

various combinations of OS and compilers, the configure script does not

always print these flags automatically.

STEP 4 You may proceed directly to testing. The Makefile will compile any files that

are needed to execute the test runs. If you want to use your own potential

energy surface, you have to add it to the Makefile. The name of the new

executable, the file name of the potential energy surface and its object have to

be added. Comments in the Makefile will help you make these additions.

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STEP 5 The following two compiling problems are common enough to merit special

mention. If you get an error relating to module libc.a(shr.o), it is probably

because other modules are interfering with the compilation. Unload any extra

modules that are running and recompile. If during the compilation of the RP-

VTST version, the installation stops because the file mpif.h cannot be found,

the user should generate a dummy file called mpif.h in the src directory (for

instance, by typing touch mpif.h <Return> in the Polyrate src directory).

.

15.A.2. Testing

The directory structure and files should be set up as instructed in Subsection 15.A.1.

Note that some of the processes described in this section may be time consuming. In a

Unix system, you can always add an ‘&’ character at the end of a command line to put

the process in the background. In the following instructions, whenever you see a

command followed by an ‘&’ character, it means that we suggest that the user run the

command in the background.

It is recommended that the user run all the test runs in the distribution package before

using POLYRATE. We have included many useful scripts to run the test runs, and you can

choose how to run the test runs from among several different approaches.

(1) To run all the test runs:

The test runs are grouped into 15 different sets, in particular, ch3, ch4cl, ch4oh, ch5,

clhbr, cmc, cwmc, h2ni, h3, h3o2, hni, ho2, nh3, oh3, and ohcl test runs. (See Subsection

16.C.) Each set has its own subdirectory in the Polyrate17/testrun directory. (See

Subsection 15.A.1.) The subdirectories contain the input data files and the job control

files for the test runs. The only thing you need to run all the test runs for either RP-VTST

or VRC-VTST is to change the working directory to the Polyrate17/testrun directory and

run the script run_allRPVTST.jc or run_allVRCVTST.jc.

./run_allRPVTST.jc & <Return>

(or submit it as a batch job)

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Note run_allRPVTST.jc and run_allVRCVTST.jc need different Makefiles.

The user has to take the steps described in Section 15.A.1 to generate a Makefile either

for VRC-VTST calculations or for RP-VTST calculations.

(2) To run a subset of the test runs

1. To run a set of test runs, use the scripts available in the testrun/ directory. For

example, to run all the h3 test runs, change the working directory to the

Polyrate17/testrun directory and use the script runh3.jc.

(change to the testrun/ directory)

./runh3.jc & <Return>

(or any of the other run{name}.jc scripts, where {name} can be ch5, oh3, ho2,

clhbr, cmc, cwmc, nh3, hni, h2ni, ch4cl, or ch4oh)

3. To run an individual test run, say ch5j1tr1, change the directory to testrun/ch5/

and use the script ch5j1tr1.jc.

./ch5j1tr1.jc & <Return>

(or any of the {test_run_name}.jc scripts in that directory)

Note: Do not run more than one test run in the same directory simultaneously.

(See Subsection 15.B, item VI.)

(3) To check the test run results:

When you finish running the test runs, you should check if they produced the correct

results by comparing the test run short output files (fu15 files) with the ones in the testo/

directory. There is a useful script, check_test.jc, in the testrun/ directory to do this after

you finish a whole set of test runs. For example, if you have finished all the oh3 test runs

and you want to compare the results with the correct ones, change the working directory

to testrun/ and type ./check_test.jc oh3 <Return>. The script will use the Unix command

diff to compare your results with the ones in the directory testo/, and generate an output

file called oh3.chk. You can then look at the contents of that file and see if there are any

differences. Since the reaction rates are not calculated in test runs ch5j2tr2 and nh3tr1,

the short output files for these two test runs are not created. Thus if you type

check_test.jc ch5 <Return>, there will be no check for ch5j2tr2. You can still use the diff

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command to compare the long output files (fu6 files) of these test runs with the ones

provided in the Polyrate17/testo directory. There is a similar script, check_all.jc, that

you can use to test the full suite of test runs.

If your test runs reproduce the results in Polyrate17/testo, the only differences will be the

date and time. Otherwise, the script will point out where the results differ from each

other. (Of course, you have to know a little bit about the diff command to understand its

output. Type man diff <Return> if you need help.) In running the test runs on different

machines, we found that the differences in the rate constants were never greater than 1%.

If your rate constant results do not differ from the ones in the Polyrate17/testo directory

by more than this percentage, they are probably correct; otherwise, something unexpected

might be happening.

(4) Cleaning up:

When you finish checking the testrun results, you may want to clean up the testrun

directory to save disk space. The script, clean_up.jc, in the Polyrate17/testrun directory

can be used to remove all the files Polyrate generated when running the test suite. These

files include the following: *.fu1, *.fu6, *.fu14, *.fu15, *.fu25, *.fu26, *.fu27, and

*.fu61.

15.A.3. Using POLYRATE

Many users will user Polyrate mainly as part of a direct dynamics calculations carried out

with GAMESSPLUSRATE, GAUSSRATE, JAGUARRATE, MC-TINKERATE, MORATE,

MULTILEVELRATE, or NWCHEMRATE. However the rest of this section is devoted to using

Polyrate as a stand-alone program.

After installation you should have the default directory structure and the correct machine-

dependent files. If you are planning to use Polyrate with a direct dynamics code, such as

GAUSSRATE or MULTILEVELRATE, read the instructions in the direct dynamics manual. If

you are planning to use Polyrate as a stand-alone code, follow the instructions in this

section:

1. Unless you are performing an electronic structure input file calculation, prepare

your own potential energy surface subroutine to do the calculations. See Section 8

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for a discussion of user-supplied potential energy surfaces. Supposing that you have

made your own potential energy surface subroutine, you need to compile it before

you link it with the Polyrate source code. This can be accomplished by adding the

surface into the Makefile located in the src directory. Comments in the Makefile

will show you where to add lines. For example, suppose you have made a surface

subroutine for a system that consists of 2 hydrogen atoms and 1 oxygen atom, and

you have put it in the Polyrate17/poten directory and named oh2.f. You have to

add the following line where the executables are defined

OH2S = ../exe/Polyrate$(VERSION).oh2.serial.exe

Then add ../poten/oh2.f to the POT: list, using a \ in order to continue a

line. Also, add the following line to compile the surface, beginning with a tab.

$(F77C) -c ../poten/oh2.f

Finally, add the lines that create the executable. Use a tab to start the second line.

OH2S:$(OBJ) dummy_mpi.o oh2.o

$(F77C) -o $(OH2) $(OBJ) dummy_mpi.o oh2.o

For three- and four-atom systems, the user can take advantage of some pre-written

subroutines, namely: setup, surf, coord, and chain. If these subroutines were not

explicitly included in the oh2.f file, the lines to create the executable would look

like this (without a break between oh2.o and setup3.o):

OH2S:$(OBJ) dummy_mpi.o oh2.o

$(F77C) -o $(OH2) $(OBJ) dummy_mpi.o oh2.o

setup3.o surf3.o coord3.o chain3.o

2. Prepare the input data files. Study Section 12 carefully to make the input data files

correctly. Because some of the input data files are quite complicated, it may be

easier to use some of the test run input data files as templates when preparing your

own input data files.

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3. Run the dynamics calculations with POLYRATE. After you finish steps 1 and 2, you

are ready to use Polyrate to do your calculations. Before you submit your job to the

computer, it is recommended that you do the following:

A. Make a directory for each specific reaction. For example, you can make a directory

called reaction in the Polyrate17 directory or somewhere else, and when you are

planning to do a calculation on a specific reaction, say O + H2, you can create a

directory called oh2 in the Polyrate17/reaction directory. You can then use this

directory as your working directory for this reaction and put all the input data files

and output files in this directory.

B. Use a job control script (.jc) to handle all the processes involved in running

POLYRATE. Polyrate only recognizes a certain set of input file names and will

generate a set of output files with certain names (see Sections 12, 15.B and 16.C),

therefore, the user always needs to copy (or link) the input data files to the default

names and rename the output files to more logical names. It is more convenient to

use a script to control these tedious processes. Using a script also makes it easier to

run the job in background or to submit the Polyrate run as a batch job. In fact, we

have included job control files for all test runs in the distribution package. You

probably used them when you ran the test runs, and you can easily modify them for

your own needs. They all reside in the subdirectories of the Polyrate17/testrun

directory. In your .jc script, be sure to change the ‘set name’ and ‘gmake’ lines to

match your job. In the OH2 example, if you decided the name your files oh2run1,

the lines would look like this:

set name = oh2run1

gmake OH2S

C. With gmake in the job control script, the executable will be compiled the first time

that it is used, and also anytime there is a change in one of the files that it is

dependent on. If a change is made to the source code, the next time that the job

control script is run, gmake will recognize that a change has been made and compile

the changed code and create a new executable. If the user does not desire this

feature, the gmake line may be deleted from the .jc job control script once the

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executable is compiled for the first time. Executables are put in the exe directory

by default.

15.B. Comments for expert users

Of course, users need not use the provided Unix scripts, files, or recommended

directory structure. All that is needed is the compilation of the source code, linking the

Polyrate object files with appropriate potential energy surface object file(s), and running

the executable file(s) with input data file(s). However, there are a few practical issues to

be aware of, as follows.

Compilation of POLYRATE

For the RP version of the code, compile

dattim.F ef.F fromlapack.F hooks.F intbsv2.F.bak ivtstm.F,

polyag.F polymq.F rtpjac.F util.f90 acespoly.F dummy_mpi.F

energetics.F givtst.F, intbsv1.F intbsv3.F main.F poly31.F

polyhl.F polyrr.F sprng_f.h vrctst_mpi.F, alloc.f90 dumpot.F

fromblas.F headr.F intbsv2.F interface.F main_vrcmpi.F

poly40.F , poly_mpi.F polysz.F torsion.f90

For the RP version of the code compile

energetics.F, givtst.F, hooks.F, intbsv1.F, intbsv2.F intbsv3.F,

interface.F, main.F, Polyrate.F, polyag.F, polyhl.F, polymq.F, polyrr.F,

polysz.F, rtpjac.F,

The POLYRATE17 program should be compiled with 64-bit precision and dynamic

memory allocation.

Compilation of the potential energy surface files

The potential energy surface subroutines provided with the Polyrate program

should be compiled with the same precision and memory specifications used for the

Polyrate source code. Any user-supplied potential energy surface subroutine must also

be compiled with 64-bit precision, but specification for static memory allocation will

depend on the way in which the subroutine is written.

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Creation of an executable file

Link the Polyrate object file with potential object file(s) to create specific

POLYRATE-potential executable file(s).

Running POLYRATE

The Polyrate program opens all the input and output files needed for a calculation

with the logical file names poly.fu#, where # is an integer. The files poly.fu5 and

poly.fu6 are always opened (they correspond to input and output files respectively). The

other poly.fu# files are opened depending on which options are set. Therefore, all the

necessary input data files must be copied or linked to files with the proper logical names.

If the user wants the output files to have different names, the renaming of the poly.fu#

output files must be performed after the calculation has completed.

Note: Because the Polyrate program opens and closes its files with the file name

specification poly.fu#, these files should be renamed at the end of each calculation, or

there will be conflicts when two calculations are run in the same directory.

In addition to the Polyrate input and output files, the user should ensure that the

potential data files, if any, which are opened by the potential energy surface

subroutine(s), have the correct file names as specified in the OPEN statement(s) in the

potential subroutine source code. For the test runs, these names are listed after "FILE

NAME =" in Subsection 16.C. Also, these data files need to be in the working directory

of the calculation.

15.C. Running in parallel using MPI

The Polyrate program has been expanded to work with multiple processors using MPI.

MPI can be very machine dependent, therefore this section will highlight the areas that

need to be correct for the parallel feature to work correctly. There are two MPI versions.

One is for calculations with MEP and the other one is for calculations with variable

reaction coordinate (VRC). These two versions need to be compiled by including

different subroutines since they use different parallel schemes.

A. MPI version for calculations with MEP

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For samples on how to make MPI work using MEP, see the CH5P sections of the

Makefile, and look at the job control scripts in the ch5 testruns. The MPI sections of the

Makefile are only printed if an MPI compiler is found by the configure script.

I. In the Makefile, MPIF77C needs to be set to the correct MPI compiler. The

poly_mpi.f source file must be compiled using this compiler, not the serial

compiler. Finally, the linking section must use the MPI compiler when creating

the executable.

II. In the job control script (*.jc file), set $nproc equal to the number of processors

you wish to use. Make sure the exe variable is set to the proper executable. Most

importantly, the platform on which you are running has a certain way that MPI

jobs must be run. By default, the line looks like this:

(time mpirun -v -np $nproc $exe) >>& $name.time

where “mpirun -v -np $nproc $exe” is the part that actually tells the

program how to run. This line will likely need to be edited to work with each

platform.

III. For an example, the testrun ch5j1tr1 has edited this line in the job control script to

work on a particular IBM regatta. The line now reads:

(time poe $exe -rmpool 1 -nodes 1 -procs

$nproc) >>& $name.time

B MPI version for calculations with VRC

When installing Polyrate program, user will be asked whether the MPI executable for

variable reaction coordinate need to be compiled by a Perl installation script under

Polyrate17 directory, named configure. This script will automatically search MPI

compiler for user. But user has to be responsible to make sure the compiler and its

options are correct in Makefile since MPI can be very machine dependent.

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Since this MPI version for variable reaction coordinate use SPRNG (SCALABLE PARALLEL

RANDOM NUMBER GENERATOR LIBRARY) package in Monte Carlo integrations, user needs

to install SPRNG before Polyrate installation. Starting with version 2010, SPRGN 2.0

package is included in Polyrate program. The Polyrate installation script will compile the

SPRNG 2.0 library before generate Makefile for VRC-VTST run. The SPRNG package can

also be downloaded from its website at the Florida State University

(http://sprng.cs.fsu.edu/) and installed separately by users. When linking object files, user

should give the correct path for SPRNG library by changing the $SPRNGLIB variable in

Makefile if user desires use separately installed SPRNG library.

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16. SAMPLE TEST RUNS

16.A. Chart of the potential energy functions and data files

The following chart gives the name of the potential energy function and data file(s) that

are used for each test run. They are files located in the Polyrate17/poten directory.

When two data files are listed for the same test run, both data files are required. The file

listed first should be assigned to unit 4, and the file listed second should be assigned to

unit 7.

TEST RUN(S) POTENTIAL SOURCE CODE POTENTIAL DATA FILE(S)

ch3tr1 ch3.F (none)

ch5j1tr1-ch5j1tr11 ch5.F potch5j1.dat

ch5j2tr1-ch5j2tr3 ch5.F potch5j2.dat

ch5fu51.tr1 ch5.F potch5j1.dat

clhbrtr1-clhbrtr4 clhbr.F (none)

cmctr1, cmctr2 cmc.F potcmc1.dat

potcmc2.dat

cwmctr1-cwmctr3 cwmc.F potcwmc3b.dat

potcwmcvib.dat

TEST RUN(S) POTENTIAL SOURCE CODE POTENTIAL DATA FILE(S)

ch4otr1 ch4o.F potch4o.dat

potch4o.inc

h3tr1-h3tr4 h3.F (none)

nh3tr1–nh3tr2 nh3.F (none)

ho2tr1–ho2tr5 ho2.F (none)

oh3tr1–oh3tr10 oh3.F (none)

hnitr1 hni.F pothni.dat

h2nitr1 h2ni.F poth2niads.dat

poth2nilat.dat

ohcltr1-ohcltr4 ohcl.F (none)

16.B. Descriptions of sample test runs

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This section contains descriptions of the sample runs which make up the Polyrate test

suite. The input data files and the summary output files from unit fu15 for the test runs

are part of the distribution package. For convenience, we have named all the test runs

according to the potential energy surface used for the test run.

The following is a list of reactions involved in the test suite and references to published

calculations of their reaction rates using POLYRATE.

CH3 + H2 → CH3

CH3 + H2 → CH4 + H see Refs. 17 and 20 in Sect. 21

CH3 + HPh → CH4 + Ph see Ref. 21 in Sect. 21

Cl + HBr → ClH + Br see Ref. 10 in Sect. 21

Cl- + CH3Cl' → ClCH3 + Cl'- see Ref. 23 in Sect. 22

Cl-(H2O) + CH3Cl' → ClCH3 + Cl'-(H2O) see Ref. 24 in Sect. 22

H2 + H' → HH' + H see Ref. 12 in Sect. 21

OH + O → HO2 see Ref. 4 in Sect. 21

O2 + H → HO2 see Ref. 4 in Sect. 21

NH3 → NH3 (inversion) see Ref. 7 in Sect. 21

OH + H2 → H2O + H see Refs. 1, 3, and 6 in Sect. 21

H(a)/Ni(100) → H(a)/Ni(100) see Ref. 33 in Sect. 22

H2(a)/Ni(100) → 2H(a)/Ni(100) see Ref. 19 in Sect. 21

OH + CH4 → H2O + CH3 see Refs. 26 and 32 in Sect. 21

Cl + CH4 → HCl + CH3 see Refs. 22 and 26 in Sect. 21

CH4 + O → CH3 + OH see Ref. 52 in Sect. 22

O + HCl → OH + Cl

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O + HCl(v=1) → OH + Cl see Refs. 22 and 26 in Sect. 21

H2O2 + H → H2O + OH

Various options were used for each of these systems to give a thorough test of POLYRATE.

Some of the most critical options used are discussed in each description; the keywords

used for these options are specified in square brackets: e. g. [KEYWORD]. The potential

energy surfaces used for the sample runs for the reaction CH3 + H2 → CH4 + H are

surfaces J1 and J2 of Joseph et al. [Ref. 17, Sect. 21]. Surface J1 is also used for the

calculations for the reaction CH3 + HPh → CH4 + Ph, where Ph denotes a single atom

with the mass of a phenyl group (see Ref. 21 in Sect. 21). The calculations for the

reaction Cl + HBr → ClH + Br use the extended LEPS surface of Babamov, Lopez, and

Marcus [Ref. 26, Sect. 22]. The calculations for the Cl-(H2Om) + CH3Cl' → ClCH3 +

Cl'-(H2Om) reactions, m = 0,1, use the potential energy surface of Tucker and Truhlar

[Ref. 23, Sect. 22] and Zhao et al. [Refs. 24 and 27, Sect. 22], while the DMBE surface of

Varandas et al. [Ref. 28, Sect. 22] is used for the reaction H2 + H' → HH' + H. The

calculations for the reaction OH + O → HO2 and O + H2 → HO2 use the ab initio surface

of Melius and Blint [Ref. 29, Sect. 22], and all the runs for the reaction OH + H2 → H2O

+ H use the Schatz-Elgersma fit to the Walch-Dunning ab initio potential energy surface

[Refs. 30 and 31, Sect. 22]. The embedded diatomics-in-molecules (EDIM) potential

with parameter set 4 of Truong et al. [Refs. 25 and 32, Sect. 22] is used for the H/Ni(100)

surface diffusion test run, and the Lee and DePristo [Ref. 33, Sect. 22] potential energy

surface, as modified by Truong et al. [Ref. 19, Sect. 21], is used for the H2/Ni(100)

system. Furthermore, both Ni surface test runs are carried out assuming that the entire

metallic subsystem on which the diatoms are absorbed is rigid. The calculations for the

reaction Cl- + CH3Cl' → ClCH3 + Cl'- use the semiempirical surface of Tucker and

Truhlar [Ref. 23, Sect. 22], and the calculations for the NH3 inversion use potential

energy surface II of Brown, Tucker, and Truhlar [Ref. 7, Sect. 21]. For the OH + CH4 →

H2O + CH3 [Ref. 32, Sect. 21] and Cl + CH4 → HCl + CH3 [Ref. 22, Sect. 21] reactions,

rate calculations are carried out using the IVTST method [Ref. 26, Sect. 21] with ab initio

data.

It should be pointed out that the results for the ClHBr and the H3 test runs will differ

from the published results. This difference occurs because the published results for those

systems were determined using another program, ABCRATE, which calculates

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anharmonicity corrections differently than POLYRATE. In particular, ABCRATE uses

curvilinear internal coordinates, and these produce quite different harmonic frequencies,

as discussed elsewhere [Ref. 25 and 41, Sect. 21].

Note that the test runs are designed to illustrate the use of the Polyrate program. No

implication is made that these runs are converged with respect to all step sizes and grid

ranges. One can use these runs to test that the code as received gives the same results on

various new platforms by comparing the output for these test runs to the distributed

output, even though the results are not necessarily converged with respect to numerical

parameters.

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16.C.1. Test run ch5j1tr1

CH3 + H2 → CH4 + H with harmonic approximation

This sample run is for the reaction CH3 + H2 → CH4 + H with the J1 potential energy

surface. All normal modes and generalized normal modes are treated using the default

harmonic approximation. The rate constants are computed using CVT and ICVT [CVT,

ICVT]. Tunneling corrections are computed using the MEPSAG, CD-SCSAG, and LCG3

methods [ZCT, SCT, SCTOPT, LCTOPT] Note that only the ground-state in the LCG3 exit

arrangement is considered for the LCG3 calculation in this run [NOALLEXCIT] this option

is chosen to simplify the calculation because we expect on physical grounds that only

ground-state-to-ground-state tunneling is important in this case. The LCT keyword was

not explicitly given since the default is on when LCTOPT is used. The rate constants are

computed for ten temperatures [TEMP], and the activation energies are computed for six

pairs of temperatures [EACT]. The MEP is followed using the Page-McIver method [RPM

= pagem] with a step size of 0.001 bohr [SSTEP]. The Hessian matrix is recalculated and

a mode analysis is performed every 0.01 bohr [INH = 100]. The curvature components

are calculated using a quadratic fit to obtain the derivative of the gradient with respect to

the reaction coordinate [CURV = dgrad]. A restart file containing reaction-path

information is written to unit fu1 [RESTART = writefu1] for use in test run ch5j1tr2.

For both reactants and the first product STATUS = 6 and the geometries, energies, and

frequencies are read from fu5, for the second product STATUS = 2 and the geometry is

read from fu5, and for the saddle point STATUS = 4 and the geometry, energy, and

Hessian are read from fu5. The reactants are input in fu5 [ENERGY, FREQ] to reduce the

number of calculations. The results may be compared to those in Table VII of Ref. 17 in

Sect. 21.

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Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5j1tr1.dat poly.fu5 input data file

ch5j1tr1.fu6 poly.fu6 long output file

ch5j1tr1.fu1 poly.fu1 reaction path info.

ch5j1tr1.fu14 poly.fu14 summary output file

ch5j1tr1.fu15 poly.fu15 summary output file

ch5j1tr1.fu61 esp.fu61 2nd restart option file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j1.dat UNIT = 4

FILE NAME = potch5.dat

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16.C.2. Test run ch5j1tr2

CH3 + H2 → CH4 + H with harmonic approximation

This sample run is for the reaction CH3 + H2 → CH4 + H with the J1 potential energy

surface. All the parameters are the same as for test run ch5j1tr1 except that the reaction-

path information is read from a restart file on unit fu1 [RESTART: readfu1]. In order to

perform this test run, the restart file must first be created by the user by running test run

ch5j1tr1.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5j1tr2.dat poly.fu5 input data file

ch5j1tr1.fu1 poly.fu1 reaction path info.

(input data for a

restart calculation)

ch5j1tr2.fu6 poly.fu6 long output file

ch5j1tr2.fu14 poly.fu14 summary output file

ch5j1tr2.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j1.dat UNIT = 4

FILE NAME = potch5.dat

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16.C.3. Test run ch5j1tr3

CH3 + H2 → CH4 + H with mass-weighted reaction coordinate

This sample run for the reaction CH3 + H2 → CH4 + H is similar to test run ch5j1tr1,

except that the reduced mass [SCALEMASS] which defines the mass-scaled Cartesian

coordinates, is set equal to the default, 1.0 amu. Thus, these coordinates have the same

numerical values as the conventional mass-weighted coordinates in infrared

spectroscopy. The vibrational partition functions are multiplied by a factor of 1 1010 to

avoid underflow [VPFEXP] ; note that these changes alone would not change the final rate

constants. In addition, though, in this run the effective mass for the CD-SCSAG

tunneling calculation is obtained by sixth-order Lagrangian interpolation [SCTOPT:

lagrange] instead of a cubic spline fit. Also, there is no LCG3 calculation in this test run.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5j1tr3.dat poly.fu5 input data file

ch5j1tr3.fu6 poly.fu6 long output file

ch5j1tr3.fu14 poly.fu14 summary output file

ch5j1tr3.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j1.dat UNIT = 4

FILE NAME = potch5.dat

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16.C.4. Test run ch5j1tr4

CH3 + H2 → CH4 + H with harmonic approximation in redundant internal

coordinates and the Page-McIver method to calculate

reaction-path curvature

This sample run for the reaction CH3 + H2 → CH4 + H demonstrates the calculation of

reaction-path curvature components from the Hessian, generalized normal mode

eigenvectors, and gradient [CURV = dhess] using eq. (48) of Page and McIver [Ref. 17,

Sect. 22]. The MEP is followed using the Euler steepest-descents (ESD) method [RPM =

esd] with a step size of 0.0001 bohr [SSTEP]. A generalized normal mode analysis is

performed every 0.01 bohr along the MEP [INH = 100], and all the vibrations are treated

harmonically in redundant internal coordinates [COORD = curv3]. Both CVT [CVT] and

ICVT [ICVT] rate constants are calculated, and tunneling corrections are computed using

both MEPSAG and CD-SCSAG methods [ZCT, SCTOPT] .

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5j1tr4.dat poly.fu5 input data file

ch5j1tr4.fu6 poly.fu6 long output file

ch5j1tr4.fu14 poly.fu14 summary output file

ch5j1tr4.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j1.dat UNIT = 4

FILE NAME = potch5.dat

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16.C.5. Test run ch5j1tr5

CH3 + HPh → CH4 + Ph with LCG3 calculation for the ground state only

This sample run is for the CH3 + HPh → CH4 + Ph reaction, where Ph denotes a single

particle with the mass of a phenyl group. The CH5 analytical potential energy surface,

J1, is used for this six-atom model problem; see Ref. 21 in Sect. 21 for further discussion.

All normal modes and generalized normal modes are treated using the default harmonic

approximation. TST, CVT, and ICVT rate constants are computed [TST, CVT, ICVT]. The

tunneling calculations for ground-state transmission coefficients are computed using the

MEPSAG, CD-SCSAG, and LCG3 methods [ZCT, SCTOPT, LCTOPT] . The program writes

a restart file containing the reaction-path information to unit fu1 for use in test run

ch5j1tr6 [RESTART = writefu1]. The MEP is followed using the ESD integrator

without stabilization (ESD method) [RPM = esd] with a step size of 0.0001 bohr [SSTEP],

and a generalized normal mode analysis is performed every 0.01 bohr [INH = 100]. The

curvature components are calculated using a quadratic fit to obtain the derivative of the

gradient with respect to the reaction coordinate [CURV = dgrad] . The results may be

compared to those in Table 5 in Ref. 21 in Sect. 21, but it should be noted that there is a

difference of a few percent between the LCG3 results in Ref. 21 and those calculated

with this data file due to improved convergence.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5j1tr5.dat poly.fu5 input data file

ch5j1tr5.fu6 poly.fu6 long output file

ch5j1tr5.fu1 poly.fu1 reaction path info.

ch5j1tr5.fu14 poly.fu14 summary output file

ch5j1tr5.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j1.dat UNIT = 4

FILE NAME = potch5.dat

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16.C.6. Test run ch5j1tr6

CH3 + HPh → CH4 + Ph with LCG3 calculation for all energetically accessible excited

states from a restart file in which the LCG3 calculation was

carried out for the ground state only; rate constants are also

calculated at more temperatures. (Restart file for unit fu1 is

from test run ch5j1tr5)

This sample run, like the preceding test run, is for the CH3 + HPh → CH4 + Ph reaction,

where Ph denotes a single particle with the mass of a phenyl group. The potential energy

surface and all the parameters are the same as for test run ch5j1tr5 except for the

tunneling calculations and the temperatures for which the rate constants are calculated.

In this run the tunneling calculations for ground-state transmission coefficients are

performed with the MEPSAG, CD-SCSAG, and LCG3 methods [ZCT, SCTOPT, LCTOPT].

For the LCG3 calculation, the program determines the highest excited state of the LCG3

exit arrangement which is accessible, and those excited states are included in the LCG3

calculation [ALLEXCIT]. The results may be compared to those from test run ch5j1tr5, in

which the LCG3 calculations were done for the ground state only; the present LCG3

transmission coefficients are up to 4% larger.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5j1tr6.dat poly.fu5 input data file

ch5j1tr5.fu1 poly.fu1 reaction path info.

(input data for a

restart calculation)

ch5j1tr6.fu6 poly.fu6 long output file

ch5j1tr6.fu14 poly.fu14 summary output file

ch5j1tr6.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j1.dat UNIT = 4

FILE NAME = potch5.dat

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16.C.7. Test run ch5j1tr7

CH3 + H2 → CH4 + H with Page-McIver mass-weighted reaction path and

IVTST0FREQ

This sample run for the reaction CH3 + H2 → CH4 + H is similar to test run ch5j1tr3,

except that the reaction-path curvature components are calculated from the Hessian,

generalized normal mode eigenvectors, and gradient [CURV = dhess] using eq. (48) of

Page and McIver [Ref. 17, Sect. 22]. The MEP is followed using the Page-McIver

method [RPM = pagem] with a step size of 0.001 bohr [SSTEP]. The Hessian matrix is

recalculated and a mode analysis is performed every 0.01 bohr [INH = 100]. The

vibrational partition functions are multiplied by a factor of 1 1010 to avoid underflow

[VPFEXP]; note that this alone would not change the final rate constants. In addition, the

effective mass for the CD-SCSAG tunneling calculation is obtained by sixth-order

Lagrangian interpolation [SCTOPT: lagrange] instead of the default cubic spline fit. Also,

there is no LCG3 calculation in this test run. The IVST0FREQ method [IVTST0FREQ] is

used to modify the 10th and 11th vibrational modes along the reaction path.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5j1tr7.dat poly.fu5 input data file

ch5j1tr7.fu6 poly.fu6 long output file

ch5j1tr7.fu14 poly.fu14 summary output file

ch5j1tr7.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j1.dat UNIT = 4

FILE NAME = potch5.dat

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16.C.8. Test run ch5j1tr8

CH3 + H2 → CH4 + H with MEPSAG and CD-SCSAG calculations at two

temperatures [one of the test cases in Ref. 27 in Sect. 21]

This sample run for the reaction CH3 + H2 → CH4 + H is one of the test cases in Ref. 27

in Sect. 21. (However, Ref. 27 used SCSAG whereas the current code uses CD-SCSAG).

The MEP is calculated from s = -1.3 bohr to s = 0.8 bohr [SRANGE] using the Euler

stabilization method [RPM = es1] . The gradient and save step sizes are all set to 0.047

bohr [SSTEP, INH = 1] The finite difference step size and the tolerance parameter in the

ES1 method are set to 0.072 (1.532*SSTEP) [ES1OPT: delta2] and 0.082 [ES1OPT: DIFFD],

respectively. The CVT/MEPSAG and CVT/CD-SCSAG rate constants are calculated

[CVT, ZCT, SCT] at 200K and 300K [TEMP]. All the rate constants are within 15% of the

converged values obtained in the test run ch5j1tr1.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5j1tr8.dat poly.fu5 input data file

ch5j1tr8.fu6 poly.fu6 long output file

ch5j1tr8.fu14 poly.fu14 summary output file

ch5j1tr8.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j1.dat UNIT = 4

FILE NAME = potch5.dat

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Polyrate 338

16.C.9. Test run ch5j1tr9

CH3 + H2 → CH4 + H with harmonic approximation

This sample run is for the reaction CH3 + H2 → CH4 + H with the J1 potential energy

surface. All normal modes and generalized normal modes are treated using the default

harmonic approximation. The rate constants are computed using CVT and ICVT [CVT,

ICVT]. Tunneling corrections are computed using the MEPSAG, CD-SCSAG, and LCG4

methods [ZCT, SCT, SCTOPT, LCTOPT] Note that only the ground-state in the LCG4 exit

arrangement is considered for the LCG4 calculation in this run [NOALLEXCIT] this option

is chosen to simplify the calculation because we expect on physical grounds that only

ground-state-to-ground-state tunneling is important in this case. The LCT keyword was

not explicitly given since the default is on when LCTOPT is used. The rate constants are

computed for ten temperatures [TEMP], and the activation energies are computed for six

pairs of temperatures [EACT]. The MEP is followed using the Page-McIver method [RPM

= pagem] with a step size of 0.001 bohr [SSTEP]. The Hessian matrix is recalculated and

a mode analysis is performed every 0.01 bohr [INH = 100]. The curvature components

are calculated using a quadratic fit to obtain the derivative of the gradient with respect to

the reaction coordinate [CURV = dgrad]. For both reactants and the first product STATUS

= 6 and the geometries, energies, and frequencies are read from fu5, for the second

product STATUS = 2 and the geometry is read from fu5, and for the saddle point STATUS =

4 and the geometry, energy, and Hessian are read from fu5. The reactants are input in fu5

[ENERGY, FREQ] to reduce the number of calculations. The results may be compared to

those in Table VII of Ref. 17 in Sect. 21.

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Polyrate 339

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5j1tr9.dat poly.fu5 input data file

ch5j1tr9.fu6 poly.fu6 long output file

ch5j1tr9.fu1 poly.fu1 reaction path info.

ch5j1tr9.fu14 poly.fu14 summary output file

ch5j1tr9.fu15 poly.fu15 summary output file

ch5j1tr9.fu61 esp.fu61 2nd restart option file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j1.dat UNIT = 4

FILE NAME = potch5.dat

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Polyrate 340

16.C.10. Test run ch5j1tr10

CH3 + HPh → CH4 + Ph with LCG4 calculation for all energetically accessible excited

states from a restart file in which the LCG4 calculation was

carried out for the ground state only; rate constants are also

calculated at more temperatures. (Restart file for unit fu1 is

from test run ch5j1tr5)

This sample run, like the preceding test run, is for the CH3 + HPh → CH4 + Ph reaction,

where Ph denotes a single particle with the mass of a phenyl group. The potential energy

surface and all the parameters are the same as for test run ch5j1tr5 except for the

tunneling calculations and the temperatures for which the rate constants are calculated.

In this run the tunneling calculations for ground-state transmission coefficients are

performed with the MEPSAG, CD-SCSAG, and LCG4 methods [ZCT, SCTOPT, LCTOPT].

For the LCG4 calculation, the program determines the highest excited state of the LCG4

exit arrangement which is accessible, and those excited states are included in the LCG4

calculation [ALLEXCIT].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5j1tr10.dat poly.fu5 input data file

ch5j1tr5.fu1 poly.fu1 reaction path info.

(input data for a

restart calculation)

ch5j1tr10.fu6 poly.fu6 long output file

ch5j1tr10.fu14 poly.fu14 summary output file

ch5j1tr10.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j1.dat UNIT = 4

FILE NAME = potch5.dat

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Polyrate 341

16.C.11. Test run ch5j1tr11

CH3 + HPh → CH4 + Ph with interpolated LCG4 calculation with all energetically

accessible excited states.

This sample run for the CH3 + HPh → CH4 + Ph is similar than the previous run where

Ph denotes a single particle with the mass of a phenyl group. The only difference with

the previous test is that the large curvature tunneling energies obtained by the LCG4

method are interpolated to 9 points in the nonadiabatic zone [ILCT1D with LCTGRD

equal to 9 for all excited states]. The ILCG4 calculation includes all the final excited

states that are accessible [ALLEXCIT]. It is interesting to compare the LCG4 transmission

factors with the ones calculated in the previous run in which NGTHETA = 180.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5j1tr11.dat poly.fu5 input data file

ch5j1tr11.fu6 poly.fu6 long output file

ch5j1tr11.fu14 poly.fu14 summary output file

ch5j1tr11.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j1.dat UNIT = 4

FILE NAME = potch5.dat

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Polyrate 342

16.C.12. Test run ch5j2tr1

CH3 + H2 → CH4 + H with harmonic approximation and ES1 method

This sample run for the reaction CH3 + H2 → CH4 + H with the J2 potential energy

surface is similar to the one described in Subsection 16.C.1. In addition to employing a

different potential energy surface, a major difference between this test run and test run

ch5j1tr1 is the method of calculating the MEP. Also, the LCG3 calculation is omitted in

this run. To calculate the MEP, a step size of 0.001 bohr is used for the first five steps

from the saddle point [SFIRST] and then a larger step size (0.01 bohr) [SSTEP] is used for

the remaining steps in combination with the Euler stabilization (ES1) method [RPM =

es1]. In addition, sixth-order Lagrangian interpolation is used to obtain the values of the

effective mass for the CD-SCSAG tunneling calculation [SCTOPT : lagrange] .

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5j2tr1.dat poly.fu5 input data file

ch5j2tr1.fu6 poly.fu6 long output file

ch5j2tr1.fu14 poly.fu14 summary output file

ch5j2tr1.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j2.dat UNIT = 4

FILE NAME = potch5.dat

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Polyrate 343

16.C.13. Test run ch5j1tr12

CH3 + HPh → CH4 + Ph with 2D interpolated LCG4 with all energetically

accessible excited states.

In this run the CH3 + HPh → CH4 + Ph thermal rate constants are calculated with the

LCT4 method with all energetically accessible vibrational excited states. As in the

previous run Ph denotes a single particle with the mass of the phenyl group. The only

difference with previous test is that both the tunneling energies and the points along each

tunneling energies are obtained from a grid specified by LCTGRD and fitted to a 2D

spline under tension [option ILCT2D in LCTOPT]. The rectangular grid was built from 7

tunneling energies and 11 points along each tunneling energy. It is interesting to compare

this run with the previous one, which uses a 1D interpolation and with test ch5j1tr10,

which corresponds to the full LCT4 calculation.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5j1tr12.dat poly.fu5 input data file

ch5j1tr12.fu6 poly.fu6 long output file

ch5j1tr12.fu14 poly.fu14 summary output file

ch5j1tr12.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j1 UNIT = 4

FILE NAME = potch5.dat

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Polyrate 344

16.C.14. Test run ch5j2tr2

CH3 + H2 → CH4 + H with MEP only

This sample run is for the reaction CH3 + H2 → CH4 + H. The RATE and TUNNEL

sections are not given so the rate constants are not calculated. The MEP is calculated

using the ESD method [RPM = esd]. The MEP information is printed [PRINTSTEP] at grid

points separated by 0.01 bohr [SSTEP]. The overall translations and rotations are projected

out at stationary points [PROJECT].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5j2tr2.dat poly.fu5 input data file

ch5j2tr2.fu6 poly.fu6 long output file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j2.dat UNIT = 4

FILE NAME = potch5.dat

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Polyrate 345

16.C.15. Test run ch5j2tr3

CH3 + H2 → CH4 + H with WKB approximation for two modes

This sample run is for the reaction CH3 + H2 → CH4 + H using a combination of

methods for treating the various normal modes [VANHAR]. All reactants and products are

treated harmonically. Along the reaction path the two lowest frequency modes are

treated using the uniform WKB method with a quadratic-quartic fit to the potential at two

input distances along the generalized normal modes [QQSEMI] and the rest of the modes

are treated using the harmonic approximation. The rate constants are calculated at five

temperatures [TEMP], and four temperature pairs are used to compute activation energies

[EACT]. Both CVT [CVT] and ICVT [ICVT] rate constants are calculated, using both

MEPSAG and CD-SCSAG tunneling corrections [ZCT, SCT]. The ESD integrator [RPM =

esd] is used to calculate the MEP, using a step size of 0.001 bohr [SSTEP]. The limits

for the MEP are determined by using two keywords: SRANGE and SPECSTOP. A

generalized normal mode analysis is performed every 0.01 bohr [INH = 10].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5j2tr3.dat poly.fu5 input data file

ch5j2tr3.fu6 poly.fu6 long output file

ch5j2tr3.fu14 poly.fu14 summary output file

ch5j2tr3.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j2.dat UNIT = 4

FILE NAME = potch5.dat

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Polyrate 346

16.C.16. Test run ch5j2itr1

CH3 + H2 → CH4 + H with zero-order IVTST approximation

This zero-order IVTST test run [IVTST0] is for the reaction CH3 + H2 → CH4 + H using

the energies, geometries, and vibrational frequencies of the reactants, saddle point, and

products from the J2 potential of Joseph et al. [Ref. 17, Sect. 21].* All reactants and

products are treated harmonically. The rate constants are calculated at four temperatures

[TEMP]. This test run reproduces the results from one of the test cases in Ref. 26 in Sect.

21.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5j2itr1.dat poly.fu5 input data file

ch5j2itr1.fu29 poly.fu29 input data file

ch5j2itr1.fu6 poly.fu6 long output file

* The data are input by means of the unit fu29 file.

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Polyrate 347

16.C.17. Test run ch5j2itr2

CH3 + H2 → CH4 + H with first-order IVTST approximation

This first-order IVTST test run [IVTST1] is for the reaction CH3 + H2 → CH4 + H using

the energies, geometries, and vibrational frequencies of the reactants, saddle point,

products, and a point on the MEP at s = 0.01 bohr from the J2 potential of Joseph et al.

[Ref. 17, Sect. 21].* All reactants and products are treated harmonically. The rate

constants are calculated at four temperatures [TEMP]. This test run reproduces the results

from one of the test cases in Ref. 26 in Sect. 21.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5j2itr2.dat poly.fu5 input data file

ch5j2itr2.fu29 poly.fu29 input data file

ch5j2itr2.fu6 poly.fu6 long output file

* The data are input by means of the unit fu29 file.

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Polyrate 348

16.C.18. Test run ch5fu29tr1

CH3 + H2 → CH4 + H zero-order IVTST reaction rate with electronic structure data

read from file fu29 and frequencies input directly.

This is a zero-order IVTST test run for the reaction CH3 + H2 → CH4 + H [IVTST0].

Electronic structure information calculated at the UHF/STO-3G level (energies and

frequencies) is read from unit fu29. At this level of electronic structure theory, CH3 is

nonplanar; therefore the symmetry number of the forward reaction is 2 [SIGMAF=2]. All

reactants and products are treated harmonically and the frequencies are in cm-1. The TST

rate constants [TST, NOCVT] are calculated at four temperatures [TEMP] with zero-

curvature transmission coefficients calculation. [ZCT] The zero-order IVTST calculation

can also be done with the fu50 option. A similar test run (ch5fu50tr1) can be used to

check the result.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu29tr1.dat poly.fu5 input data file

ch5fu29tr1.fu29 poly.fu29 input data file

ch5fu29tr1.fu6 poly.fu6 long output file

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Polyrate 349

16.C.19. Test run ch5fu29tr2

CH3 + H2 → CH4 + H zero-order IVTST reaction rate with information read from fu29

and Hessian matrix input in packed form

This is a zero-order IVTST test run [TST, CVT] for the reaction CH3 + H2 → CH4 + H

[IVTST0]. Electronic structure information calculated at the UHF/STO-3G level

(Hessians of reactants, saddle point, and products in packed format) is read from file

fu29. At this level of electronic structure theory, CH3 is nonplanar; therefore the

symmetry number of the forward reaction is 2 [SIGMAF=2]. All reactants and products

are treated harmonically. Hessians and geometries are input in unscaled Cartesian

coordinates in bohrs. The rate constants are calculated at four temperatures [TEMP]. A

similar calculation has been done in the ch5tr29tr1 and ch5fu50tr1 test runs.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu29tr2.dat poly.fu5 input data file

ch5fu29tr2.fu29 poly.fu29 input data file

ch5fu29tr2.fu6 poly.fu6 long output file

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Polyrate 350

16.C.20. Test run ch5fu30tr1

CH3 + H2 → CH4 + H TST reaction rate with frequencies read from fu30 directly

This is a conventional TST test run for the reaction CH3 + H2 → CH4 + H [NOCVT and

TST]. Electronic structure information calculated at the UHF/STO-3G level (energies and

frequencies of reactants, saddle point, and products) is read from file fu30 [POTENTIAL =

unit30]. At this level of electronic structure theory, CH3 is nonplanar; therefore the

symmetry number of the forward reaction is 2 [SIGMAF=2]. Harmonic frequencies of

reactants and products are input in atomic units [LOPT(4) = 0 in unit fu30]. The rate

constants are calculated at four temperatures [TEMP].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu30rt1.dat poly.fu5 input data file

ch5fu30tr1.fu30 poly.fu30 input data file

ch5fu30tr1.fu6 poly.fu6 long output file

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Polyrate 351

16.C.21. Test run ch5fu30tr2

CH3 + H2 → CH4 + H TST reaction rate with information read from fu30 and full

Hessian matrices input

This is a conventional TST test run for the reaction CH3 + H2 → CH4 + H [NOCVT and

TST]. Electronic structure information calculated at the UHF/STO-3G level (energies and

full matrix format Hessians of reactants, saddle point, and products) is read from file fu30

[POTENTIAL = unit30]. At this level of electronic structure theory, CH3 is nonplanar;

therefore the symmetry number of the forward reaction is 2 [SIGMAF=2]. All reactants

and products are treated harmonically. Hessians and geometries are input in unscaled

Cartesian coordinates in atomic units [LOPT(4) = 1 and LOPT(3) = 0, respectively, in unit

fu30]. The rate constants are calculated at four temperatures [TEMP].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu30tr2.dat poly.fu5 input data file

ch5fu30tr2.fu30 poly.fu30 input data file

ch5fi30tr2.fu6 poly.fu6 long output file

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Polyrate 352

16.C.22. Test run ch5fu30tr3

CH3 + H2 → CH4 + H TST reaction rate with information read from fu30 and Hessian

matrix input in packed form

This is a conventional TST test run for the reaction CH3 + H2 → CH4 + H [NOCVT and

TST]. Electronic structure information calculated at the UHF/STO-3G level (energies and

Hessians of reactants, saddle point, and products in packed format) is read from file fu30

[POTENTIAL = unit30]. At this level of electronic structure theory, CH3 is nonplanar;

therefore the symmetry number of the forward reaction is 2 [SIGMAF=2]. All reactants

and products are treated harmonically (some anharmonicity options are not supported for

conventional TST calculations in POLYRATE–2017). Hessians are input in unscaled

Cartesian coordinates in atomic units [LOPT(4) = -1 in unit fu30]. The rate constants are

calculated at four temperatures [TEMP].

The electronic structure information for this run was generated with the GAMESS

electronic structure package (Aug. 11, 1994 – IBM version), which yields an H2

stretching frequency of 5479.11 cm-1. POLYRATE, with this input, yields 5479.18 cm-1.

The GAUSSIAN94 electronic structure package yields a slightly different Hessian and a

frequency of 5478.64 cm-1.

Notice that the Hessian for H2 corresponds to the molecule being on the z-axis, whereas

the geometry corresponds to the molecule being on the y-axis. For calculating reactant

frequencies this does not matter, but such an inconsistency would matter along the

reaction path (see Section 9.B). It is worthwhile to point out that commonly-available

electronic structure packages may, by default, re-orient a molecule before computing its

Hessian.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu30tr3.dat poly.fu5 input data file

ch5fu30tr3.fu30 poly.fu30 input data file

ch5fu30tr3.fu6 poly.fu6 long output file

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Polyrate 353

16.C.23. Test run ch5fu30tr4

CH3 + H2 → CH4 + H TST reaction rate with information read from fu30 and

frequencies input directly

This is a conventional TST test run for the reaction CH3 + H2 → CH4 + H [NOCVT and

TST]. Electronic structure information (energies and frequencies of the reactants, the

products, and the saddle point) at the QCISD/6-311G(d, p) level is read from file fu30

[POTENTIAL = unit30]. (The VMEP(s) has been scaled by a factor of 0.86 to be

consistent with Ref. 48 in Section 22. The scaling was done by hand; however, the

VSCALE keyword could have been used instead of hand scaling) At this level of electronic

structure theory, CH3 is planar; therefore the symmetry number of the forward reaction is

4 [SIGMAF=4]. Harmonic frequencies of reactants and products are input in atomic units

and geometries are input in unscaled Cartesian coordinates in bohrs. The rate constants

are calculated at twelve temperatures [TEMP].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu30tr4.dat poly.fu5 input data file

ch5fu30tr4.fu30 poly.fu30 input data file

ch5fu30tr4.fu6 poly.fu6 long output file

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Polyrate 354

16.C.24. Test run ch5fu30tr5

CH3 + H2 → CH4 + H TST and CVT reaction rates with information along the reaction

path read from fu30

This is a sample run that illustrates the use of electronic structure input file data from unit

fu30 [POTENTIAL = unit30] in the calculation of rate constants for the reaction CH3 +

H2 → CH4 + H. Electronic structure information read from file fu30 (energies,

geometries, and Hessians of reactants, saddle point, products and a series of 60 points

along the reaction path) was calculated at the UHF/STO-3G level using GAMESS for

generating the reaction path (ES1 integrator, mass-weighted Cartesian coordinates, step

size = 0.005 amu1/2 a0) and GAUSSIAN94 for calculating the unscaled forces and Hessians

(run with geometry input in Cartesian coordinates and the NOSYMM keyword on) at the

generalized TST structures every 0.05 amu1/2 bohr along the reaction path. The strategy

for producing the electronic structure data was carefully selected in order to avoid the

reorientation of geometries along the reaction path though the different steps of the

process. At this level of electronic structure theory, CH3 is nonplanar; therefore the

symmetry number of the forward reaction is 2 [SIGMAF=2]. Geometries and forces are

input in unscaled Cartesian coordinates in atomic units [LOPT(3) = 100 in unit fu30].

Hessians are also input in unscaled Cartesian coordinates in bohr using the packed format

as obtained from the GAUSSIAN94 formatted checkpoint file [LOPT(4) = 99]. All normal

modes are treated harmonically and TST, CVT, and ICVT rate constants [CVT and ICVT]

are calculated at four temperatures [TEMP], using both MEPSAG and CD-SCSAG

tunneling transmission factors [ZCT, SCT]. Curvature components are calculated using the

derivative of the gradient with respect to s obtained from a quadratic fit of the gradient at

three points on the basic input grid [LOPT(6) = 2] which is also called the sparse input

grid. Note that the results obtained with this test run differ from those previously

reported in Ref. 20 in Sect. 21. Several errors were detected in Ref. 20 (see Section 24.B

in this manual for the corresponding errata).

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu30tr5.dat poly.fu5 input data file

ch5fu30tr5.fu30 poly.fu30 input data file

ch5fu30tr5.fu6 poly.fu6 long output file

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Polyrate 355

16.C.25. Test run ch5fu30tr6

CH3 + H2 → CH4 + H TST and CVT reaction rates with information along the

reaction path read from fu30. Frequencies evaluated in

redundant internal coordinates.

This is a sample run that illustrates the use of electronic structure input file data from unit

fu30 [POTENTIAL = unit30] in the calculation of rate constants for the reaction CH3 +

H2 → CH4 + H. Electronic structure information calculated at the UHF/STO-3G level

following the procedure explained in test run ch5fu30tr5 (energies, geometries, and

Hessians of reactants, products, saddle point, and a series of 50 points along the reaction

path) is read from file fu30. At this level of electronic structure theory, CH3 is

nonplanar; therefore the symmetry number of the forward reaction is 2 [SIGMAF=2].

Geometries and forces are input in unscaled Cartesian coordinates in atomic units

[LOPT(3) = 100 in unit fu30]. Hessians are also input in unscaled Cartesian coordinates in

atomic units using the packed format as obtained from the GAUSSIAN94 formatted

checkpoint file [LOPT(4) = 99]. All normal modes are treated harmonically in redundant

internal coordinates [COORD = curv3], and TST, CVT, and ICVT rate constants [CVT

and ICVT] are calculated at four temperatures [TEMP], using both MEPSAG and CD-

SCSAG tunneling transmission factors [ZCT, SCT].

The ‘Cartesian Forces’ from the GAUSSIAN94 formatted checkpoint file are actually

Cartesian Gradients; use of them as forces will introduce errors in the transformation

from rectilinear to curvilinear internal coordinates. Also, the gradients (or forces) must

be un-normalized in order to carry out the transformation correctly.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu30tr6.dat poly.fu5 input data file

ch5fu30tr6.fu30 poly.fu30 input data file

ch5fu30tr6.fu6 poly.fu6 long output file

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Polyrate 356

16.C.26. Test run ch5fu31tr1

CH4 + H → CH3 + H2 IVTST-M-56/6 calculation using fu31

This sample run performs a IVTST-M-56/6 calculation using an fu31 input file. The

curvature components are interpolated, the vibrational analysis is carried out in redundant

internal coordinates, and ICVT rate constants are calculated. The information in the fu31

input file was obtained from the J1 potential energy surface by means of the WRITEFU31

keyword. Only the forward rate constant were calculated.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu31tr1.dat poly.fu5 input data file

ch5fu31tr1.fu31 poly.fu31 input data file

ch5fu31tr1.fu6 poly.fu6 long output file

ch5fu31tr1.fu15 poly.fu15 summary output file

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Polyrate 357

16.C.27. Test run ch5fu40tr1

CH3 + H2 → CH4 + H TST reaction rate with frequencies read from fu40 directly

This is a conventional TST test run for the reaction CH3 + H2 → CH4 + H [NOCVT and

TST]. Electronic structure information calculated at the UHF/STO-3G level (energies,

and frequencies of reactants, saddle point, and products) is read from file fu40

[POTENTIAL = unit40]. At this level of electronic structure theory, CH3 is nonplanar;

therefore the symmetry number of the forward reaction is 2 [SIGMAF=2]. Harmonic

frequencies of reactants, products, and saddle point are input in atomic units

[FREQSOURCE = read and FREQUNIT = au in unit fu40] and geometries are input in

unscaled Cartesian coordinates in bohrs [GEOMUNIT = bohr in unit fu40]. The rate

constants are calculated at four temperatures [TEMP].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu40rt1.dat poly.fu5 input data file

ch5fu40tr1.fu40 poly.fu40 input data file

ch5fu40tr1.fu6 poly.fu6 long output file

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Polyrate 358

16.C.28. Test run ch5fu40tr2

CH3 + H2 → CH4 + H TST reaction rate with information read from fu40 and full

Hessian matrix for frequency input

This is a conventional TST test run for the reaction CH3 + H2 → CH4 + H [NOCVT and

TST]. Electronic structure information calculated at the UHF/STO-3G level (energies and

full matrix format Hessians [HESSFORM = full ] of reactants, saddle point, and products)

is read from file fu40 [POTENTIAL = unit40]. At this level of electronic structure

theory, CH3 is nonplanar; therefore the symmetry number of the forward reaction is 2

[SIGMAF=2]. All reactants and products are treated harmonically. Hessians and

geometries are input in unscaled Cartesian coordinates in atomic units [HESSUNIT = bohr

and GEOMUNIT = bohr, respectively, in unit fu40]. The rate constants are calculated at

four temperatures [TEMP].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu40tr2.dat poly.fu5 input data file

ch5fu40tr2.fu40 poly.fu40 input data file

ch5fi40tr2.fu6 poly.fu6 long output file

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Polyrate 359

16.C.29. Test run ch5fu40tr3

CH3 + H2 → CH4 + H TST reaction rate with information read from fu40 and Hessian

matrix input in packed form

This is a conventional TST test run for the reaction CH3 + H2 → CH4 + H [NOCVT and

TST]. Electronic structure information calculated at the UHF/STO-3G level (energies and

Hessians of reactants, saddle point, and products in packed format [HESSFORM =

packed]) is read from file fu40 [POTENTIAL = unit40]. At this level of electronic

structure theory, CH3 is nonplanar; therefore the symmetry number of the forward

reaction is 2 [SIGMAF=2]. All reactants and products are treated harmonically. Hessians

and geometries are input in unscaled Cartesian coordinates in bohrs [HESSUNIT = bohr

and GEOMUNIT = bohr, respectively, in unit fu40]. The rate constants are calculated at

four temperatures [TEMP].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu40tr3.dat poly.fu5 input data file

ch5fu40tr3.fu40 poly.fu40 input data file

ch5fu40tr3.fu6 poly.fu6 long output file

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Polyrate 360

16.C.30. Test run ch5fu40tr4

CH3 + H2 → CH4 + H TST reaction rate with information read from fu40 and

frequencies input directly.

This is a conventional TST test run for the reaction CH3 + H2 → CH4 + H [NOCVT and

TST]. Electronic structure information (energies and frequencies of reactants, saddle

point, and products) at the QCISD/6-311G(d, p) level is read from file fu40 [POTENTIAL =

unit40]. (The VMEP(s) has been scaled by a factor of 0.86 to be consistent with Ref. 48

in Section 22. The scaling was done by hand; however, the VSCALE keyword could have

been used instead of hand scaling) At this level of electronic structure theory, CH3 is

planar; therefore the symmetry number of the forward reaction is 4 [SIGMAF=4].

Harmonic frequencies of reactants and products are input in wavenumbers [FREQSOURCE

= read, FREQUNIT = waven]. The rate constants are calculated at twelve temperatures

[TEMP].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu40tr4.dat poly.fu5 input data file

ch5fu40tr4.fu40 poly.fu40 input data file

ch5fu40tr4.fu6 poly.fu6 long output file

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Polyrate 361

16.C.31. Test run ch5fu40tr5

CH3 + H2 → CH4 + H TST and CVT reaction rates with information along the

reaction path read from fu40

This is a sample run that illustrates the use of electronic structure input file data from unit

fu40 [POTENTIAL = unit40] in the calculation of rate constants for the reaction CH3 +

H2 → CH4 + H. Electronic structure information read from file fu40 (energies,

geometries, and Hessians of reactants, products, saddle point, and a series of 60 points

along the reaction path) was calculated at the UHF/STO-3G level using GAMESS for

generating the reaction path (ES1 integrator, mass-weighted Cartesian coordinates, step

size = 0.005 amu1/2 a0) and GAUSSIAN94 for calculating the unscaled forces and Hessians

(run with geometry input in Cartesian coordinates and the NOSYMM keyword on) at the

generalized TST structure every 0.05 amu1/2 bohr along the reaction path. The strategy

for producing the electronic structure data was carefully selected in order to avoid the

reorientation of geometries along the reaction path through the different steps of the

process. At this level of electronic structure theory, CH3 is nonplanar; therefore the

symmetry number of the forward reaction is 2 [SIGMAF=2]. Geometries and forces are

input in unscaled Cartesian coordinates in atomic units [GEOMUNIT = bohr and

GRADUNIT = bohr, respectively, in unit fu40]. Hessians are also input in unscaled

Cartesian coordinates in atomic units using the packed format as obtained from the

GAUSSIAN94 formatted checkpoint file [HESSUNIT = bohr and HESSFORM = packed].

All normal modes are treated harmonically and TST, CVT, and ICVT rate constants [CVT

and ICVT] are calculated at four temperatures [TEMP], using both MEPSAG and CD-

SCSAG tunneling transmission factors [ZCT, SCT]. Curvature components are calculated

using the derivative of the gradient with respect to s obtained from a quadratic fit of the

gradient at three points on the basic input grid [CURVATURE = compute, GRADDER =

noextra], which is also called the sparse input grid. Note that the results obtained with

this test run differ from those previously reported in Ref. 20 in Sect. 21. Several errors

were detected in Ref. 20 (see Section 24.B in this manual for the corresponding errata).

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Polyrate 362

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu40tr5.dat poly.fu5 input data file

ch5fu40tr5.fu40 poly.fu40 input data file

ch5fu40tr5.fu6 poly.fu6 long output file

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Polyrate 363

16.C.32. Test run ch5fu40tr6

CH3 + H2 → CH4 + H TST and CVT reaction rates with information along the reaction

path read from fu40. Frequencies are evaluated with redundant

internal coordinates.

This is a sample run that illustrates the use of electronic structure input file data from unit

fu40 [POTENTIAL = unit40] in the calculation of rate constants for the reaction CH3 +

H2 → CH4 + H. Electronic structure information calculated at the UHF/STO-3G level

following the procedure explained in test run ch5fu40tr5 (energies, geometries, and

Hessians of reactants, saddle point, products and a series of 50 points along the reaction

path) is read from file fu40. At this level of electronic structure theory, CH3 is

nonplanar; therefore the symmetry number of the forward reaction is 2 [SIGMAF=2].

Geometries and forces are input in unscaled Cartesian coordinates in atomic units

[GEOMUNIT = bohr and GRADUNIT = bohr, respectively, in unit fu40]. Hessians are

also input in unscaled Cartesian coordinates in atomic units using the packed format as

obtained from the GAUSSIAN94 formatted checkpoint file [HESSUNIT = bohr and

HESSFORM = packed]. All normal modes are treated harmonically in redundant internal

coordinates [curv3] and TST, CVT and ICVT rate constants [CVT and ICVT] are

calculated at four temperatures [TEMP], using both MEPSAG and CD-SCSAG tunneling

transmission factors [ZCT, SCT].

The quantities labeled as “Cartesian forces” in the GAUSSIAN94 formatted checkpoint file

are actually Cartesian gradients, and using them as forces will introduce errors in the

transformation from rectilinear to curvilinear internal coordinates. Also, the gradients (or

forces) must be un-normalized in order to carry out the transformation correctly.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu40tr6.dat poly.fu5 input data file

ch5fu40tr6.fu40 poly.fu40 input data file

ch5fu40tr6.fu6 poly.fu6 long output file

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Polyrate 364

16.C.33. Test run ch5fu50tr1

CH3 + H2 → CH4 + H zero-order IVTST reaction rate with information read from fu50

and frequencies input directly.

This is a conventional TST test run for the reaction CH3 + H2 → CH4 + H [NOCVT and

TST]. Electronic structure information calculated at the UHF/STO-3G level is read from

file fu50 [IC in unit fu5 and 0IVTST in unit fu50]. All reactants and products are treated

harmonically and the frequencies are in put in cm-1 [RCFREQA, PCFREQA, SADFREQA, and

FREQIMAG]. A rate constants are calculated at four temperatures [TEMP]. The similar

calculation can be performed with the fu29 option. Both the ch5fu29tr1 and ch5fu29tr2

test runs can be used for checking the output from different input methods.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu50tr1.dat poly.fu5 input data file

ch5fu50tr1.fu50 poly.fu50 input data file

ch5fu50tr1.fu6 poly.fu6 long output file

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Polyrate 365

16.C.34. Test run ch5fu50tr2

CH3 + H2 → CH4 + H VTST-IOC dual-level reaction rate calculation with information

for the higher level read from fu50 and J1 analytic surface as the

lower level.

This is a VTST-IOC test run for the reaction CH3 + H2 → CH4 + H using an analytic

surface as the lower level [IC and POTENTIAL = hooks]. The potential energy is not

corrected in the nonadiabatic region in the LCT calculation [LCTCOR = nocor].

Electronic structure information calculated at the UHF/STO-3G level is read from file

fu50 and the lower-level information is obtained from the J1 surface. All the parameters

are the same as for test run ch5j1tr1.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu50tr2.dat poly.fu5 input data file

ch5fu50tr2.fu50 poly.fu50 input data file

ch5fu50tr2.fu6 poly.fu6 long output file

ch5fu50tr2.fu14 poly.fu14 summary output file

ch5fu50tr2.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j1.dat UNIT = 4

FILE NAME = potch5.dat

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Polyrate 366

16.C.35. Test run ch5fu50tr3

CH3 + H2 → CH4 + H VTST-IOC dual-level reaction rate calculation with information

for the higher level read from fu50 and J1 analytic surface as the

lower level.

This is a VTST-IOC test run for the reaction CH3 + H2 → CH4 + H using an analytic

surface as the lower level [IC and POTENTIAL = hooks]. The potential energy is

corrected in the nonadiabatic region in the LCT calculation based on a quadratic

correction [LCTCOR = quadlin]. Electronic structure information calculated at the

UHF/STO-3G level is read from file fu50 and the lower-level information is obtained

from the J1 surface. All the parameters are the same as for test run ch5j1tr1.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu50tr3.dat poly.fu5 input data file

ch5fu50tr3.fu50 poly.fu50 input data file

ch5fu50tr3.fu6 poly.fu6 long output file

ch5fu50tr3.fu14 poly.fu14 summary output file

ch5fu50tr3.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j1.dat UNIT = 4

FILE NAME = potch5.dat

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Polyrate 367

16.C.36. Test run ch5fu51tr1

CH3 + H2 → CH4 + H VTST-ISPE calculation with MP2/6-31G** and J1

This is a VTST-ISPE test run for the reaction CH3 + H2 → CH4 + H using an analytic

surface as the lower-level [dl and potential = hooks]. Electronic structure information

calculated at the MPS/6-31G** level is read in from file fu51 and the lower-level

information is obtained from the J1 surface. Two extra points plus the stationary points

used for the VTST-ISPE calculation were obtained from single-point energy calculations

at the MP2/6-31G** level with the configurations obtained from the lower-level surface.

All the parameters for the lower-level are the same as for the test run ch5j1tr1.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu51tr1.dat poly.fu5 input data file

ch5fu51tr1.fu51 poly.fu51 VTST-

ISPE input file

ch5fu51tr1.fu6 poly.fu6 long output

file

ch5fu51tr1.fu14 poly.fu14

summary output file

ch5fu51tr1.fu15 poly.fu15

summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potch5j1.dat UNIT=4

FILE NAME=potch5.dat

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Polyrate 368

16.C.37. Test run ch5icfu30tr1

CH3 + H2 → CH4 + H VTST-ICL-DECKART calculation using file fu30 for the lower

level information and rectilinear coordinates

This sample run uses the unit30 [POTENTIAL = unit30] and the IOC [ICOPT: icl,

deckart] options to invoke a dual-level direct dynamics calculation (variational

transition state theory with interpolated optimized corrections) on the reaction CH3 + H2

→ CH4 + H. The lower-level reaction path file is constructed at the UHF/STO-3G level,

and the higher-level interpolated optimized corrections are calculated from the

QCISD(T)/6-311G(d, p) level results. (The VMEP(s) has been scaled by a factor of 0.86 to

be consistent with Ref. 48 in Section 22. The scaling was done by hand; however, the

VSCALE keyword could have been used instead of hand scaling) All the modes are treated

harmonically. Cartesian coordinates are used [COORD = cart]. Both small-curvature

and zero-curvature tunneling calculations are carried out [ZCT, SCT]. The interpolated

optimized correction is based on the logarithm of ratios [ICOPT: icl] and an Eckart fit is

used to the energies at 3 stationary points (i.e. reactants, products, and saddle point)

[ICOPT: deckart]. At the higher level of electronic structure theory employed, CH3 is

planar; therefore the symmetry number of the forward reaction is 4 [SIGMAF=4].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5icfu30tr1.dat poly.fu5 input data file

ch5icfu30tr1.fu30 poly.fu30 input data file

ch5icfu30tr1.fu50 poly.fu50 input data file

ch5icfu30tr1.fu6 poly.fu6 output file

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Polyrate 369

16.C.38. Test run ch5icfu30tr2

CH3 + H2 → CH4 + H VTST-IOC calculation using file fu30 for the lower level

information and curvilinear coordinates

This sample run uses the unit30 option [POTENTIAL = unit30] and the IOC [ICOPT:

ica, seckart] options to invoke a dual-level direct dynamics calculation with

interpolated optimized corrections on the reaction CH3 + H2 → CH4 + H. The lower-

level reaction path file is constructed at the UHF/STO-3G level, and the higher-level

interpolated optimized corrections are calculated from the QCISD(T)/6-311G(d, p) level

results. (The VMEP(s) has been scaled by a factor of 0.86 to be consistent with Ref. 48 in

Section 22. The scaling was done by hand; however, the VSCALE keyword could have

been used instead of hand scaling) The original ICA interpolated correction method is

used for the IC method. At the higher level of electronic structure theory employed, CH3

is planar; therefore the symmetry number of the forward reaction is 4 [SIGMAF = 4].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5icfu30tr2.dat poly.fu5 input data file

ch5icfu30tr2.fu30 poly.fu30 input data file

ch5icfu30tr2.fu50 poly.fu50 input data file

ch5icfu30tr2.fu6 poly.fu6 output file

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Polyrate 370

16.C.39. Test run ch5icfu31tr1

CH4 + H → CH3 + H2 VTST-IOC calculation using IVTST-M-56/6 data

for the lower level of calculation and using the fu31

input file

This sample test run uses the unit31 and the IOC options to perform a dual level direct

dynamics calculation with interpolated optimized corrections. The lower level is an

IVTST-M-6/56 calculation based on the information from a fu31 input file. The higher-

level interpolated optimized corrections are calculated at the QCISD(T)/6-311G(d, p)

level with VMEP(s) scaled by a factor of 0.86, as taken from Ref. 48 in Section 22. The

ICA method is used for the correction of the frequencies, and the SECKART option is used

for the energy correction.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu31tr1.dat poly.fu5 input data file

ch5fu31tr1.fu31 poly.fu31 input data file

ch5fu31tr1.fu50 poly.fu50 input data file

ch5fu31tr1.fu6 poly.fu6 long output file

ch5fu31tr1.fu15 poly.fu15 summary output file

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Polyrate 371

16.C.40. Test run ch5icfu40tr1

CH3 + H2 → CH4 + H VTST-ICL-DECKART calculation using file fu40 for the

lower level information and rectilinear coordinates

This sample run uses the unit40 [POTENTIAL = unit40] and the IC [ICOPT: icl,

deckart] options to invoke a dual-level direct dynamics calculation (variational

transition state theory with interpolated optimized corrections) on the reaction CH3 + H2

→ CH4 + H. The lower-level reaction path file is constructed at the UHF/STO-3G level,

and the higher-level interpolated optimized corrections are calculated from the

QCISD(T)/6-311G(d, p) level results with VMEP(s) scaled by a factor of 0.86 taken from

Ref. 48 in Section 22. All the modes are treated harmonically. Cartesian coordinates are

used [COORD = cart]. Both small-curvature and zero-curvature tunneling calculations

are carried out [ZCT, SCT]. The interpolated correction is based on the logarithm of ratios

[ICOPT: icl]. At the higher level of electronic structure theory employed, CH3 is planar;

therefore the symmetry number of the forward reaction is 4 [SIGMAF = 4].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5icfu40tr1.dat poly.fu5 input data file

ch5icfu40tr1.fu40 poly.fu40 input data file

ch5icfu40tr1.fu50 poly.fu50 input data file

ch5icfu40tr1.fu6 poly.fu6 output file

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Polyrate 372

16.C.41. Test run ch5icfu40tr2

CH3 + H2 → CH4 + H VTST-IOC calculation using file fu40 for the lower level

information

This sample runuses the unit40 [POTENTIAL = unit40] and the IOC [ICOPT: ica,

seckart] options to invoke a dual-level direct dynamics calculation with interpolated

optimized corrections on the reaction CH3 + H2 → CH4 + H. The lower-level reaction

path file is constructed at the UHF/STO-3G level, and the higher-level interpolated

optimized corrections are calculated from the QCISD(T)/6-311G(d, p) level results with

VMEP(s) scaled by a factor of 0.86 taken from Ref. 48 in Section 22. The original ICA

interpolated correction procedure is used for the IOC method. At the higher level of

electronic structure theory employed, CH3 is planar; therefore the symmetry number of

the forward reaction is 4 [SIGMAF = 4].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5icfu40tr2.dat poly.fu5 input data file

ch5icfu40tr2.fu40 poly.fu40 input data file

ch5icfu40tr2.fu50 poly.fu50 input data file

ch5icfu40tr2.fu6 poly.fu6 output file

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Polyrate 373

16.C.42. Test run clhbrtr1

Cl + HBr → HCl + Br with LCG3 calculations for all energetically accessible excited states in the LCG3 exit arrangement, and with the zero of energy

of the reactants determined by the program

This sample run is for the reaction Cl + HBr → HCl + Br with an extended LEPS surface.

All modes are treated using the default harmonic approximation. TST and CVT rate

constants are computed [TST, CVT]. The tunneling calculations of ground-state

transmission coefficients are performed using the MEPSAG, CD-SCSAG, and LCG3

methods [ZCT, SCT, LCTOPT]. The MEP is followed with the ESD integrator [RPM = esd]

with a step size of 0.00001 bohr [SSTEP], and a generalized normal mode analysis is

performed every 0.01 bohr [INH = 1000]. For the LCG3 calculation, the highest

energetically open vibrational state in the LCG3 exit arrangement (HCl + Br) is

determined and then all open vibrational states are included in the tunneling calculations

[ALLEXCIT] . (As always, for LCG3 calculations only the ground state is considered for

the LCG3 entrance arrangement, which is the reactant arrangement of the exoergic

direction.) Also, the theta integrals, the vibrationally adiabatic potential, the vibrational

period, and the sine of the angle between the MEP and the tunneling path at NGS0 points

between each pair of adjacent energy quadrature points are obtained by 2-point

interpolation [LCTOPT: interpolate]. This is done because the adiabatic potential of

the first vibrational excited state is not monotonic on the reactant side and, therefore,

unphysical results are obtained using interpolation with an order higher than 2. The

curvature components are calculated using a quadratic fit to obtain the derivative of the

gradient with respect to the reaction coordinate [CURV = dgrad]. The zero of energy of

the reactants is calculated from the energies of the individual molecular reactant species;

in other words, the default value of EZERO = calculate is used. Note that the

degeneracies and energies of the 2P3/2 and 2P1/2 states of Cl and Br are used in the

calculation of the reactant and product electronic partition functions. However, for the

transition state only the ground electronic state needs to be considered, because all

excited electronic states are too high in energy to have a significant effect.

The results differ from those in Ref. 10 in Sect. 21 because Ref. 10 included

anharmonicity and treated the bend in curvilinear internal coordinates, whereas the

present run is harmonic and treats all vibrations in mass-scaled Cartesians. The treatment

in Ref. 10 in Sect. 21 is more reliable.

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Polyrate 374

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

clhbrtr1.dat poly.fu5 input data file

clhbrtr1.fu6 poly.fu6 long output file

clhbrtr1.fu14 poly.fu14 summary output file

clhbrtr1.fu15 poly.fu15 summary output file

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Polyrate 375

16.C.43. Test run clhbrtr2

Cl + HBr → HCl + Br with LCG3 calculations in which n = 3 is the highest excited state that is included in the LCG3 exit arrangement, and with the

zero of energy of the reactants specified in the input

This sample run is similar to the clhbrtr1 test run. All vibrational modes are treated using

the default harmonic approximation. TST and CVT rate constants are computed [TST,

CVT]. The tunneling calculations of ground-state transmission coefficients are performed

using the MEPSAG, CD-SCSAG, and LCG3 methods [ZCT, SCT, LCTOPT]. For the LCG3

calculation, the n = 0, 1, 2, and 3 vibrational states in the LCG3 exit arrangement (HCl +

Br) are included in the tunneling calculation [EXCITED = 3]. The highest energetically

open vibrational state Npmax

is determined [Ref. 30 in Sect. 21], and the LCG3 tunneling

calculation includes the n = 0 to min[3, Npmax

] vibrational states in the LCG3 exit

arrangement. (For LCG3 calculations, only the ground state is considered for the LCG3

entrance arrangement, which is the reactant arrangement of the exoergic direction.) The

MEP is followed by the ESD method [RPM = esd] with a step size of 0.00001 bohr

[SSTEP] and a generalized normal mode analysis is performed every 0.01 bohr [INH =

1000]. Just as for test run clhbrtr1, we use 2-point interpolation [LCTOPT:

interpolate] for the various quantities needed in the LCG3 calculations. The

curvature components are calculated using a quadratic fit to obtain the derivative of the

gradient with respective to the reaction coordinate [CURV = dgrad]. The energy of the

reactants, which is taken as the overall zero of energy, is read from unit fu5 [EZERO =

read]. The results should be the same as those obtained in the clhbrtr1 test run.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

clhbrtr2.dat poly.fu5 input data file

clhbrtr2.fu6 poly.fu6 long output file

clhbrtr2.fu14 poly.fu14 summary output file

clhbrtr2.fu15 poly.fu15 summary output file

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Polyrate 376

16.C.44. Test run clhbrtr3

Cl + HBr → HCl + Br with LCG4 calculation for all the energetically accessible excited states in the LCG4 exit rearrangement, and with the zero of

energy determined by the program

This sample is similar to the clhbrtr1 run. All vibrational modes are treated within the

harmonic approximation. The only difference with test run clhbrtr1 is that large

curvature transmission coefficients are obtained using the LCG4 method. At each

tunneling energy a number of points along the straight path is NGTHETA = 140. The

LCG4 tunneling probabilities are evaluated at NGAMP = 40 tunneling paths.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

clhbrtr3.dat poly.fu5 input data file

clhbrtr3.fu6 poly.fu6 long output file

clhbrtr3.fu14 poly.fu14 summary output file

clhbrtr3.fu15 poly.fu15 summary output file

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16.C.45. Test run clhbrtr4

Cl + HBr → HCl + Br with interpolated LCG4 calculation for all the energetically accessible excited states in the LCG4 exit rearrangement, and

with the zero of energy determined by the program

This sample is similar to the previous clhbrtr3 test run. All vibrational modes are treated

within the harmonic approximation. The difference with the previous run is that an

interpolation is carried out, at each tunneling energy, by a splines-under-tension

procedure. In this case only 3 points were considered at each tunneling energy

[keywords ILCT and NILCGIT = 3]. Two of the three points are located at the beginning of

the nonadiabatic region and the third point is located at half the distance between the two

limiting points. This procedure still makes use of the keyword NGTHETA = 140 but the in

needed values are produced by the spline interpolation procedure. As in the previous run

the calculation takes into account all the possible open vibrational states of the exit

channel.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

clhbrtr4.dat poly.fu5 input data file

clhbrtr4.fu6 poly.fu6 long output file

clhbrtr4.fu14 poly.fu14 summary output file

clhbrtr4.fu15 poly.fu15 summary output file

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16.C.46. Test run clhbr1tr5

Cl + HBr → HCl + Br with interpolated LCG4 calculation with all the energetically

accessible excited states in the LCG4 exit rearrangement. Restart

from test run clhbrtr3.

This sample is the similar to the previous test run. The only differences are that this test

run makes use of the ILCG2D interpolation option and that a restart file is used to build

the 2D rectangular grid. In this case a quite rough grid of 5 5 is specified by LCTGRD.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

chbrtr5.dat poly.fu5 input data file

chbrtr5.fu6 poly.fu6 long output file

chbrtr5.fu14 poly.fu14 summary output file

chbrtr5.fu15 poly.fu15 summary output file

chbrtr5.fu48 poly.fu48 LCT restart file

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16.C.47. Test run cmctr1

Cl- + CH3Cl ́→ ClCH3 + Cl -́ with harmonic approximation and ES method

This sample run for the reaction Cl- + CH3Cl ́→ ClCH3 + Cl -́ uses the default harmonic

approximation for all vibrational modes. The MEP is calculated by the ESD integrator

[RPM = esd] with a step size of 0.005 bohr [SSTEP], and a generalized normal mode

analysis is performed every 0.025 bohr [INH = 5]. Both CD-SCSAG and MEPSAG

tunneling probabilities are calculated [ZCT, SCT].

This test run and the next one (cmctr2) form a pair. This one must be run before the next

one to find the s values of the wells that correspond to complexes on the reactant and

product sides of the MEP. The interpolation in test run cmctr2 on both sides of the MEP

is based on these wells, and thus we must first find the s values at these wells. A

relatively long range of the MEP (s = -7.1 bohr to s = 7.1 bohr) is calculated [SRANGE]

and we find that the s values at the wells are approximately 7.0 bohr and -7.0 bohr. We

also learn from this run that in order for the tunneling calculation to converge, the MEP

should be calculated at least from s = -1.5 bohr to s = 1.5 bohr. The saddle point

frequencies match the frequencies of the complexes in descending order (except for the

one corresponding to the reaction coordinate). We then use the information above

together with some ab initio data to make the input data file for the VTST-IOC

calculation in the cmctr2 test run.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

cmctr1.dat poly.fu5 input data file

cmctr1.fu6 poly.fu6 long output file

cmctr1.fu14 poly.fu14 summary output file

cmctr1.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potcmc1.dat UNIT = 4

FILE NAME = potcmc1.dat

potcmc2.dat UNIT = 7

FILE NAME = potcmc2.dat

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16.C.48. Test run cmctr2

Cl- + CH3Cl ́→ ClCH3 + Cl -́ harmonic approximation and VTST-IOC calculation

This sample run is similar to the cmctr1 test run except we perform a VTST-IOC

calculation in addition to the VTST calculation [ICOPT] .

This reaction has two reactants and two products, but the interpolation on both sides of

the saddle point is based on wells that correspond to complexes. We set the complex

corresponding to the well on the product side to be the product so we can get its

properties, and thus we set MEPTYPER to well and MEPTYPEP to one. The correct

energy, frequency, and moment-of-inertia-tensor determinant information at reactants,

products, saddle point, and the ion-molecule complexes are obtained from the

calculations of Tucker and Truhlar [Ref. 34, Sect. 22]. The FREQMAT keyword is used,

and the frequency matching information and the s value for the ion-molecule complex are

obtained from the cmctr1 test run. The range parameters for the unit fu50 input are

obtained by the utility programs findl.f and findb.f (see Subsection 17.D) by using

additional points on the MEP that have an energy halfway between the energy of the

saddle point and the energy of reactant- or product-side stationary point.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

cmctr2.dat poly.fu5 input data file

cmcic.dat poly.fu50 input data file

cmctr2.fu6 poly.fu6 long output file

cmctr2.fu14 poly.fu14 summary output file

cmctr2.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potcmc1.dat UNIT = 4

FILE NAME = potcmc1.dat

potcmc2.dat UNIT = 7

FILE NAME = potcmc2.dat

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16.C.49. Test run cmctr3

Cl- + CH3Cl ́→ ClCH3 + Cl -́ VTST-ISPE correction with MP2/6-31G**

This sample test run for the reaction Cl- + CH3Cl ́→ ClCH3 + Cl -́ uses the default

harmonic approximation for all vibrational modes. The MEP is followed by the Euler

steepest-descents integrator [ESD] with a step size of 0.005 bohr [SSTEP], and a

generalized normal mode analysis is performed every 5 gradient steps [ INH]. Both CD-

SCSAG and MEPSAG tunneling probabilities are calculated [ZCT, SCT].

This test run corrects the energies along the MEP by the VTST-ISPE method. The

energies of two extra points plus the stationary points were evaluated at the MP2/6-

31G** level with the configuration taken from the potential energy surface. The MEP is

calculated from s = -1.5 bohr to s = 1.5 bohr.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

cmctr3.dat poly.fu5 input data file

cmctr3.fu31 poly.fu51 VTST-ISPE input file

cmctr3.fu6 poly.fu6 long output file

cmctr3.fu14 poly.fu14 summary output file

cmctr3.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potcmc1.dat UNIT = 4

FILE NAME = potcmc1.dat

potcmc2.dat UNIT = 7

FILE NAME = potcmc2.dat

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Polyrate 382

16.C.50. Test run cwmctr1

Cl-(H2O) + CH3Cl ́→ ClCH3 . Cl -́(H2O) TST rate constants only

In this sample run the reactant, product, and saddle point properties for the reaction Cl-

(H2O) + CH3Cl ́→ ClCH3 . Cl -́(H2O), where Cl-(H2O) represents a chloride ion in the

presence of a water molecule, are calculated, and only forward TST rate constants [TST,

FORWARDK, NOCVT] are determined. No transmission coefficients are calculated nor is

the minimum energy path determined (RATE and TUNNEL sections are not used). All

normal modes and generalized normal modes are treated using the default harmonic

approximation.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

cwmctr1.dat poly.fu5 input data file

cwmctr1.fu6 poly.fu6 long output file

cwmctr1.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILES

potcwmc3b.dat UNIT = 4 FILE NAME = potcwmc3b.dat

potcwmcvib.dat UNIT = 7 FILE NAME =

potcwmcvib.dat

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Polyrate 383

16.C.51. Test run cwmctr2

Cl-(H2O) + CH3Cl ́→ ClCH3 . Cl -́(H2O) with the hindered-internal-rotator

approximation

In this sample run for the same reaction as in the cwmctrl test run, the torsional mode of

the generalized transition state is treated with the hindered-internal-rotator

approximation [VANHAR, TOR]; all other modes are treated harmonically (default). The

ESD integrator [RPM = esd] with a step size of 0.001 bohr [SSTEP] is used to follow the

MEP, and a generalized normal mode analysis is performed every 0.01 bohr [INH = 10].

The curvature components are calculated using a quadratic fit to obtain the derivative of

the gradient with respect to the reaction coordinate [CURV = dgrad]. A restart file

containing reaction-path information is written to unit fu1 [RESTART: WRITEFU1]. Rate

constants are computed using CVT only [CVT]. The tunneling corrections are computed

using the MEPSAG and CD-SCSAG methods [ZCT, SCT]. The rate constants are

calculated for the same six temperatures as in the cwmctr1 test run [TEMP].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

cwmctr2.dat poly.fu5 input data file

cwmctr2.fu6 poly.fu6 long output file

cwmctr2.fu1 poly.fu1 reaction path info.

cwmctr2.fu14 poly.fu14 summary output file

cwmctr2.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILES

potcwmc3b.dat UNIT = 4 FILE NAME = potcwmc3b.dat

potcwmcvib.dat UNIT = 7 FILE NAME = potcwmcvib.dat

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16.C.52. Test run cwmctr3

Cl-(H2O) + CH3Cl ́→ ClCH3 . Cl -́(H2O) with the hindered-internal-rotator

approximation

In this sample run for the same reaction as in the cwmctrl test run, the torsional mode of

the generalized transition state is treated with the hindered-internal-rotator approximation

with Pitzer’s algorithm for the moment of inertia [VANHAR, TOR] and with 3=P and

31 =s ; all other modes are treated harmonically (which is the default). The ESD

integrator [RPM = esd] with a step size of 0.001 bohr [SSTEP] is used to follow the MEP,

and a generalized normal mode analysis is performed every 0.01 bohr [INH = 10]. The

curvature components are calculated using a quadratic fit to obtain the derivative of the

gradient with respect to the reaction coordinate [CURV = dgrad]. A restart file

containing reaction-path information is written to unit fu1 [RESTART: WRITEFU1]. Rate

constants are computed using CVT only [CVT]. The tunneling corrections are computed

using the MEPSAG and CD-SCSAG methods [ZCT, SCT]. The rate constants are

calculated for the same six temperatures as in the cwmctr1 test run [TEMP].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

cwmctr3.dat poly.fu5 input data file

cwmctr3.fu6 poly.fu6 long output file

cwmctr3.fu1 poly.fu1 reaction path info.

cwmctr3.fu14 poly.fu14 summary output file

cwmctr3.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILES

potcwmc3b.dat UNIT = 4 FILE NAME = potcwmc3b.dat

potcwmcvib.dat UNIT = 7 FILE NAME = potcwmcvib.dat

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16.C.53. Test run h3tr1

H2 + H ́→ HH ́+ H with WKB and Morse IIIa approximations and Page-McIver

integrator

This sample run uses the Page-McIver method [RPM = pagem] for calculating points

along the MEP of the reaction H2 + H ́→ HH ́+ H with a step size of 0.01 bohr [SSTEP] ,

evaluates the Hessian matrix and performs a generalized normal mode analysis at every

calculated point [INH = 1]. Note that the generalized transition state is restricted to linear

symmetry [SPECIES = lints]. Two different methods are used to treat the vibrational

modes [VANHAR]; vibrational modes of the reactant and product molecules and the

highest frequency mode of the generalized transition state are treated by the Morse IIIa

approximation [MORSE, MORMODEL = morseiiia], while the two lowest vibrational

modes of the generalized transition state are treated by the uniform WKB method applied

to a quadratic-quartic fit to the potential along the normal mode coordinate [QQSEMI].

Extrapolation to both reactant and product limits is performed [EXFIRST, EXSECOND].

Both CVT [CVT] and ICVT [ICVT] rate constants are calculated only in the forward

direction [FORWARDK] using both MEPSAG and CD-SCSAG tunneling corrections [ZCT,

SCT], which are computed with two equal segments in the Boltzmann and theta integrals

[NSEGBOLTZ = 2, NSEGTHETA = 2].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

h3tr1.dat poly.fu5 input data file

h3tr1.fu6 poly.fu6 long output file

h3tr1.fu14 poly.fu14 summary output file

h3tr1.fu15 poly.fu15 summary output file

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16.C.54. Test run h3tr2

H2 + H ́→ HH ́+ H with harmonic approximation and Page-McIver integrator

This sample run uses the Page-McIver method [RPM = pagem] for calculating points

along the MEP of the reaction H2 + H ́→ HH ́+ H with a step size of 0.005 bohr

[SSTEP], evaluates the Hessian matrix and performs a generalized normal mode analysis

at every 0.01 bohr [INH = 2]. The generalized transition states are restricted to linear

symmetry [SPECIES = lints]. All vibrational modes are treated by the default harmonic

approximation. Both CVT [CVT] and ICVT [ICVT] rate constants are calculated only in

the forward direction [FORWARDK], using MEPSAG, CD-SCSAG, and LCG3

transmission coefficients [ZCT, SCT, LCTOPT], in which only the ground state is included in

the LCG3 exit arrangement [NOALLEXCIT]. (We expect on physical grounds that only the

ground state needs to be considered in this case, so this option is chosen to simplify the

calculation.) The overall translations and rotations are projected out at stationary points;

this is not necessary at stationary points, but it does improve the stability of the

calculations.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

h3tr2.dat poly.fu5 input data file

h3tr2.fu6 poly.fu6 long output file

h3tr2.fu14 poly.fu14 summary output file

h3tr2.fu15 poly.fu15 summary output file

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16.C.55. Test run h3tr3

H2 + H ́→ HH ́+ H with harmonic approximation, Page-McIver integrator, and

symmetric reaction path option

This sample run is the same as test run h3tr2 except that the symmetric reaction-path

option [SYMMETRY] is used, and LCG3 transmission coefficients are not calculated, i.e.,

only MEPSAG and CD-SCSAG transmission coefficients are calculated [ZCT, SCT].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

h3tr3.dat poly.fu5 input data file

h3tr3.fu6 poly.fu6 long output file

h3tr3.fu14 poly.fu14 summary output file

h3tr3.fu15 poly.fu15 summary output file

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16.C.56. Test run h3tr4

H2 + H ́→ HH ́+ H with WKB and Morse IIIa approximations, Page-McIver

integrator, and symmetric reaction path option

This sample run is the same as test run h3tr1 except that the symmetric reaction-path

option is used [SYMMETRY].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

h3tr4.dat poly.fu5 input data file

h3tr4.fu6 poly.fu6 long output file

h3tr4.fu14 poly.fu14 summary output file

h3tr4.fu15 poly.fu15 summary output file

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16.C.57. Test run ho2tr1

OH + O → HO2 with Morse I approximation

In this sample run, CVT, VT, and US rate constants [CVT, MUVT, MUVTOPT, US] are

calculated at two temperatures [TEMP] for the reaction OH + O → HO2. (The values of

the conventional transition state theory rate constants, not computed in this sample

calculation because there is no saddle point ([STATUS = 2] in START section and

NOSADDLE in the PATH section), are set to 1.0 in the unit fu15 output.) The first step off

the starting point is followed along the negative of the gradient direction [FIRSTSTEP =

gradi]. All vibrational modes are treated by the Morse I approximation [MORSE,

MORMODEL = morsei] The MEP is followed from the input initial geometry of the

reactants by the ESD method [RPM = esd] with a step size of 0.0001 bohr [SSTEP], and a

generalized normal mode analysis is performed every 0.031 bohr [INH = 310]. Both

CD-SCSAG and MEPSAG tunneling corrections are calculated [ZCT, SCT]. Note that the

reverse rate constants are scaled by a factor of 1 15 [REVKEXP = 15]. Thirty

quadrature points were used in calculating the VT rate constants. Note that the

degeneracies and energies of the 23/2 and 21/2 states of OH and 3P2, 3P1, and 3P0 states

of O are used in the calculation of the electronic partition functions. The results may be

compared to those in Table V of Ref. 4 in Sect. 21.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ho2tr1.dat poly.fu5 input data file

ho2tr1.fu6 poly.fu6 long output file

ho2tr1.fu14 poly.fu14 summary output file

ho2tr1.fu15 poly.fu15 summary output file

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16.C.58. Test run ho2tr2

OH + O → HO2 with Morse I approximation using curvilinear coordinates

In this sample run, CVT, VT, and US rate constants [CVT, MUVT, MUVTOPT, US] are

calculated at two temperatures [TEMP] for the reaction OH + O → HO2 using curvilinear

coordinates (O-H and O-O stretches and an H-O-O bend). (The values of the

conventional transition state theory rate constants, not computed in this sample

calculation because there is no saddle point [STATUS = 2 in START section and NOSADDLE

in the PATH section], are set to 1.0 in the unit fu15 output.) The MEP is followed from

the input initial geometry of the reactants by the ESD method [RPM = esd] with a step

size of 0.0001 bohr [SSTEP], and a generalized normal mode analysis is performed every

0.031 bohr [INH = 310]. Both CD-SCSAG and MEPSAG tunneling corrections are

calculated [ZCT, SCT]. Note that the reverse rate constants are scaled by a factor of

1 15 [REVKEXP = 15].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ho2tr2.dat poly.fu5 input data file

ho2tr2.fu6 poly.fu6 long output file

ho2tr2.fu14 poly.fu14 summary output file

ho2tr2.fu15 poly.fu15 summary output file

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16.C.59. Test run ho2tr3

OH + O → HO2 with WKB approximation for one mode

This sample run for the reaction OH + O → HO2 uses a combination of methods for the

treatment of the vibrational modes [VANHAR]. All modes of the reactant and product

species are treated by the default harmonic approximation. The lowest frequency mode

of the generalized transition state is also treated harmonically, while the highest

frequency mode is treated by the primitive WKB method applied to a quadratic-quartic fit

of the potential along the normal mode coordinate [QQWKB]. (The values of the

conventional transition state theory rate constants, not computed in this sample

calculation because there is no saddle point [STATUS = 2 in START section and NOSADDLE

in the PATH section], are set to 1.0 in the unit fu15 output). Points along the MEP are

calculated with the ESD integrator [RPM = esd] with a step size of 0.0001 bohr [SSTEP].

A generalized normal mode analysis, together with a Hessian matrix evaluation, is

performed every 0.155 bohr [INH = 1550]. A generalized normal mode analysis is also

performed at eight special save points [SSPECIAL]. CVT [CVT] and ICVT [ICVT] rate

constants are calculated at one temperature [TEMP], using both MEPSAG and

CD-SCSAG tunneling corrections [ZCT, SCT]. Sixth-order Lagrangian interpolation is

used to obtain the values of the effective mass for CD-SCSAG tunneling [SCTOPT:

lagrange]. The reverse rate constants are scaled by a factor of 1 15 [REVEXP =

15]. Also, restart information is written to unit fu1 [RESTART: WRITEFU1].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ho2tr3.dat poly.fu5 input data file

ho2tr3.fu6 poly.fu6 long output file

ho2tr3.fu1 poly.fu1 reaction path info.

ho2tr3.fu14 poly.fu14 summary output file

ho2tr3.fu15 poly.fu15 summary output file

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16.C.60. Test run ho2tr4

O2 + H→ HO2 with Morse I approximation

This sample run for the reaction O2 + H → HO2 uses the Morse I approximation for all

vibrational modes [MORSE, MORMODEL = morsei]. The MEP is calculated by the ESD

integrator [RPM = esd] with a step size of 0.0002 bohr [SSTEP], and a generalized normal

mode analysis is performed every 0.01 bohr [INH = 50]. Both CD-SCSAG and MEPSAG

tunneling probabilities are calculated [ZCT, SCT].

This test run forms a set with the ho2tr5 test run. Since the MEP is finite on the product

side of the saddle point and the next test run involves a VTST-IOC calculation, before

running it we must find the s value at the product. Thus, in this run we calculate a

relatively long range of the MEP (s = –2.5 bohr to s = 2.5 bohr) [SRANGE] and find that

the s value at the product is approximately 2.20 bohr. We also learn from this test run that

in order for the tunneling calculation to converge, the MEP should be calculated at least

from s = –1.8 bohr to s = 0.8 bohr. Finally we learn that the highest saddle point

frequency becomes the reactant frequency at s = –, and the second and third highest

saddle point frequencies become the product frequencies at s = 2.20 bohr. The lowest

product frequency corresponds to the reaction coordinate. We then use the information

above together with some ab initio data to make the input data file for the VTST-IOC

calculation in test run ho2tr5.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ho2tr4.dat poly.fu5 input data file

ho2tr4.fu6 poly.fu6 long output file

ho2tr4.fu14 poly.fu14 summary output file

ho2tr4.fu15 poly.fu15 summary output file

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16.C.61. Test run ho2tr5

O2 + H→ HO2 with Morse I approximation and VTST-IOC calculation

This sample run is similar to the ho2tr4 test run except we perform a VTST-IOC

calculation in addition to the VTST calculation [ICOPT].

This reaction has two reactants and one product and a shallow well on the reactant side of

MEP. In this test run we neglect the well and set the MEPTYPER to two and MEPTYPEP to

one. The accurate energy and frequency information and the geometry for calculating

the determinant of the moment of inertia tensor at the reactants and product are obtained

from J. Chem. Phys. 74, 3482 (1981). The corrected barrier height is set to 1.0 kcal/mol

and the corrected saddle point frequencies are obtained by interpolating the correction at

reactants and product. Frequency matching information is input by the FREQMAT

keyword. We use the DETMI keyword to input the corrected determinant of the moment

of inertia tensor, and we use UNITMI to select atomic units input. The frequency-matching

information and the s value for the product are obtained from the test run ho2tr4. The

range parameters in the unit fu50 input are determined by the utility programs findl.f and

findb.f (see Subsection 17.D) by using additional points on the MEP that have energies

halfway between the energy of the saddle point and the energies of the reactant- and

product-side stationary points.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ho2tr5.dat poly.fu5 input data file

ho2ic.dat poly.fu50 input data file

ho2tr5.fu6 poly.fu6 long output file

ho2tr5.fu14 poly.fu14 summary output file

ho2tr5.fu15 poly.fu15 summary output file

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16.C.62. Test run nh3tr1

NH3 → NH3 (inversion) with harmonic approximation and VTST-IOC calculation

This sample run is for the unimolecular reaction corresponding to the unimolecular

inversion of ammonia between two pyramidal configurations, using the default harmonic

approximation for all vibrational modes. The MEP is calculated by the ESD method

[RPM = esd] between s = 1.18 bohr and s = –1.18 bohr [SRANGE] with a step size of

0.0001 bohr [SSTEP]. A generalized normal mode analysis is performed every 0.01 bohr

[INH = 100]. MEPSAG and CD-SCSAG tunneling probabilities are calculated [ZCT,

SCT], and they can be used to study the tunneling splitting in this reaction. Rate constants

are not calculated [NOTST, NOCVT].

The VTST-IOC option is selected [ICOPT] and the accurate energy and frequency

information and the geometry for calculating the determinant of the moment of inertia

tensor are obtained from J. Chem. Phys. 93, 6570 (1990). The range parameters in the

unit fu50 input are determined by the utility programs findl.f and findb.f (see Subsection

17.D) by using additional points on the MEP that have an energy halfway between the

energy of the saddle point and the reactant/product energy.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

nh3tr1.dat poly.fu5 input data file

nh3ic.dat poly.fu50 input data file

nh3tr1.fu6 poly.fu6 long output file

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Polyrate 395

16.C.63. Test run nh3tr2

NH3 → NH3 (inversion) with harmonic approximation VTST calculation

This sample run is for the unimolecular reaction corresponding to the unimolecular

inversion of ammonia between two pyramidal configurations, using the default harmonic

approximation for all vibrational modes. The MEP is calculated by the ESD method

[RPM = esd] between s = 1.18 bohr and s = –1.18 bohr [SRANGE] with a step size of

0.0001 bohr [SSTEP]. A generalized normal mode analysis is performed every 0.01 bohr

[INH = 100]. The TST and CVT rate constants are calculated. The partition functions

and the internal free energy of reactant are printed out with PRPART = rpt. The GTLOG

keyword is used so the generalized free energy of activation is calculated using

logarithms of the individual partition functions.

This is a somewhat artificial example (because it is a degenerate rearrangement and

because ordinary pressures are too low to stabilize the system in on or another well), it is

used for testing the code.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

nh3tr2.dat poly.fu5 input data file

nh3tr2.fu6 poly.fu6 input data file

nh3tr2.fu14 poly.fu14 summary output file

nh3tr2.fu15 poly.fu15 summary output file

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Polyrate 396

16.C.64. Test run oh3tr1

OH + H2 → H2O + H with harmonic approximation and using the VRP(ESD)

algorithm

This sample run is for the OH + H2 → H2O + H reaction. The zero of energy of the

reactants is calculated from the energies of the individual molecular reactant species; in

other words, the default value of EZERO = calculate is used. All normal modes and

generalized normal modes are treated using the default harmonic approximation. The

VRP(ESD) algorithm [RPM = vrpe] with a step size of 0.001 bohr [SSTEP] is used to

follow the MEP, while the initial step from the saddle point is based on a cubic expansion

of the potential energy surface [FIRSTSTEP = cubic]. The first five steps from the saddle

point geometry in each direction are of size 0.0001 bohr [SFIRST]. The Hessian matrix is

recalculated and a generalized normal mode analysis is performed every 0.01 bohr [ INH =

10].

MEPSAG and CD-SCSAG tunneling corrections [ZCT, SCT] are computed, and both CVT

[CVT] and ICVT [ICVT] rate constants are calculated at eight temperatures [TEMP]. The

derivative of the gradient with respect to the reaction coordinate is found by a quadratic

fit [CURV = dgrad]. In addition, in this test run as well as in test runs oh3tr2–oh3tr6,

extrapolation is used for the first direction from the saddle point (i.e., toward reactants)

[EXFIRST] .

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3tr1.dat poly.fu5 input data file

oh3tr1.fu6 poly.fu6 long output file

oh3tr1.fu14 poly.fu14 summary output file

oh3tr1.fu15 poly.fu15 summary output file

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Polyrate 397

16.C.65. Test run oh3tr2

OH + H2 → H2O + H with Morse I-quadratic-quartic approximation

This sample run for the OH + H2 → H2O + H reaction uses the Morse I and quadratic-

quartic approximations [MORSEQQ, MORMODEL = morsei] for the normal and

generalized normal modes, i.e., modes with nonzero cubic anharmonicity are treated by

the Morse I model, while modes with zero cubic anharmonicity are approximated as

quadratic-quartic oscillators. Both the CVT [CVT] and ICVT [ICVT] methods are used.

The rate constants are calculated at twelve temperatures [TEMP] and the activation

energies are computed for three temperature pairs [EACT]. The ESD integrator [RPM =

esd] with a step size of 0.0001 bohr [SSTEP] is used to follow the MEP, and a

generalized normal mode analysis is performed every 0.01 bohr [INH = 100]. Both

MEPSAG and CD-SCSAG tunneling corrections [ZCT, SCT] are computed. Note that the

derivative of the gradient with respect to the reaction coordinate is computed by the one-

sided difference method [CURV = oneside] and the free energy of activation profile is

calculated over a different range of reaction coordinate for each temperature [GTEMP].

The results can be compared to those in Table IV of Ref. 1 in Sect. 21.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3tr2.dat poly.fu5 input data file

oh3tr2.fu6 poly.fu6 long output file

oh3tr2.fu14 poly.fu14 summary output file

oh3tr2.fu15 poly.fu15 summary output file

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Polyrate 398

16.C.66. Test run oh3tr3

OH ( = 0) + H2 → H2O + H with WKB and harmonic approximations

This sample run for the OH ( = 0) + H2 → H2O + H reaction uses the WKB

approximation for the ground-state energy of all normal modes [WKB], and the default

harmonic approximation for all excited-state energies. The overall translations and

rotations are not projected out at stationary points [NOPROJECT]. The MEP is followed

with the Euler stabilization (ES1) integrator [RPM = es1], with a step size of 0.001 bohr

[SSTEP], and the initial step from the saddle point is based on a cubic expansion of the

energy surface [FIRSTSTEP = cubic]. A value different from the default value for the

stabilization criterion (magnitude of the vector difference between successive gradients)

is used; it is set equal to 0.001 [ES1OPT: diffd]. A generalized normal mode analysis is

performed every 0.02 bohr [INH = 20]. CVT [CVT] and ICVT [ICVT] rate constants are

calculated at eight temperatures [TEMP]. Both MEPSAG and CD-SCSAG tunneling

corrections are calculated [ZCT, SCTOPT], and the curvature components are found by

using a quadratic fit to obtain the derivative of the gradient with respect to the reaction

coordinate [CURV = dgrad]. Sixth-order Lagrangian interpolation is used to obtain the

values of the effective mass for the CD-SCSAG tunneling calculation [SCTOPT:

LAGRANGE].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3tr3.dat poly.fu5 input data file

oh3tr3.fu6 poly.fu6 long output file

oh3tr3.fu14 poly.fu14 summary output file

oh3tr3.fu15 poly.fu15 summary output file

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Polyrate 399

16.C.67. Test run oh3tr4

Adiabatic OH ( = 0) + H2( = 1) → H2O + H with Morse I quadratic-quartic

approximation

This sample run is an example of the calculation of adiabatic state-selected rate constants

[STATE = adiab] for the reaction OH ( = 0) + H2( = 1) → H2O + H. The highest-

frequency normal mode of the generalized transition state is restricted to the first excited

state, while the second highest frequency mode is restricted to the ground state. All other

normal modes of the generalized transition state are treated thermally. For the reactants,

the stretching mode of OH is restricted to the ground state, and the stretching mode of H2

is restricted to the first excited state. Finally, for the product H2O, the highest normal

mode is restricted to the excited state, the second highest mode is restricted to the ground

state, and the lowest mode is treated thermally. The Page-McIver local-quadratic

approximation integrator [RPM = pagem] with a step size of 0.001 bohr [SSTEP] is used to

follow the MEP, the Hessian matrix is recalculated and a generalized normal mode

analysis is performed every 0.01 bohr [INH = 10]. All other options and input are the

same as for test run oh3tr2 except that only the forward rate constants are calculated

[FORWARDK].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3tr4.dat poly.fu5 input data file

oh3tr4.fu6 poly.fu6 long output file

oh3tr4.fu14 poly.fu14 summary output file

oh3tr4.fu15 poly.fu15 summary output file

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Polyrate 400

16.C.68. Test run oh3tr5

Diabatic OH + H2( = 1) → H2O + H with Morse I quadratic-quartic

approximation

This sample run is an example of the calculation of diabatic state-selected rate constants

[STATE = diab] for the reaction OH + H2( = 1) → H2O + H.

The adiabatic/diabatic switch occurs at s = -0.31 bohr. For s < -0.31 bohr, the highest and

second-highest frequency normal modes of the generalized transition state are restricted

to the first excited and ground state, respectively. For s > -0.31 bohr, the highest-

frequency normal mode is restricted to the ground state, while the second-highest normal

mode is restricted to the first excited state. The lowest three normal modes of the GTS

are all treated thermally for all values of s. For the reactants, the OH stretch vibration is

restricted to the ground state, while the H2 vibration is restricted to the first excited state.

The highest and second-highest frequency normal modes of the product H2O are

restricted to the ground state and first excited state, respectively, while the lowest normal

mode is treated thermally. Other options are the same as those for test run oh3tr2, except

that only forward rate constants are calculated [FORWARDK] and the free energies are

calculated over the same range of s for all temperatures [GSPEC]. The results may be

compared to those in Table I of Ref. 3 in Sect. 21.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3tr5.dat poly.fu5 input data file

oh3tr5.fu6 poly.fu6 long output file

oh3tr5.fu14 poly.fu14 summary output file

oh3tr5.fu15 poly.fu15 summary output file

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Polyrate 401

16.C.69. Test run oh3tr6

OH + H2 → H2O + H with harmonic approximation and the ES1 integrator

This sample run is for the OH + H2 → H2O + H reaction. All normal modes and

generalized normal modes are treated using the default harmonic approximation. The

ES1* integrator [RPM = es1, ES1OPT: DELTA2 = SSTEP and DIFFD = 0.01] with a step size

of 0.01 bohr [SSTEP] is used to follow the MEP, while the initial step from the saddle

point is based on a cubic expansion of the potential energy surface [FIRSTSTEP = cubic].

The Hessian matrix is recalculated and a generalized normal mode analysis is performed

every 0.01 bohr [INH = 1].

MEPSAG and CD-SCSAG tunneling corrections [ZCT, SCT] are computed, and both CVT

[CVT] and ICVT [ICVT] rate constants are calculated at eight temperatures [TEMP]. The

derivative of the gradient with respect to the reaction coordinate is found by a quadratic

fit [CURV = dgrad].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3tr6.dat poly.fu5 input data file

oh3tr6.fu6 poly.fu6 long output file

oh3tr6.fu14 poly.fu14 summary output file

oh3tr6.fu15 poly.fu15 summary output file

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Polyrate 402

16.C.70. Test run oh3tr7

OH + H2 → H2O + H with MEPSAG and CD-SCSAG calculations at two temperatures

(one of the test cases in Ref. 27 in Sect. 21), WRITEFU30 option

This sample run for the OH + H2 → H2O + H reaction is taken from one of the test cases

in Ref. 27 in Sect. 21. (However, Ref. 27 used the obsolete SCSAG method whereas the

current code uses CD-SCSAG.) The MEP is calculated from s = -1.0 bohr to s = 0.3 bohr

[SRANGE] using the Page-McIver method [RPM = pagem] with the cubic starting

algorithm [FIRSTSTEP = cubic]. The gradient and save step sizes are both set to 0.062

bohr [SSTEP, INH = 1]. The CVT/MEPSAG and CVT/CD-SCSAG rate constants are

calculated [CVT, ZCT, SCT] at 200K and 300K [TEMP]. All the rate constants are within

15% of the converged values obtained in the test run oh3tr1. Also, a file is written out in

unit fu30 format as an electronic structure input file with the WRITEFU30 option. The

points are not in the required ascending order. Therefore, this generated fu30 file needs

to be reordered by the user before using the file.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3tr7.dat poly.fu5 input data file

oh3tr7.fu6 poly.fu6 long output file

oh3tr7.fu14 poly.fu14 summary output file

oh3tr7.fu15 poly.fu15 summary output file

tr7old.fu30 poly.fu30 old fu30 file

oh3tr7.fu30 poly.fu30 reordered fu30 file

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Polyrate 403

16.C.71. Test run oh3tr8

OH + H2 → H2O + H with MEPSAG and CD-SCSAG calculations at two

temperatures, one of the test cases in Ref. 27 in Sect. 21, using

curvilinear internal coordinates

This sample run for the OH + H2 → H2O + H reaction is taken from one of the test cases

in Ref. 27 in Sect. 21. (However, Ref. 27 used the obsolete SCSAG method, whereas the

current code uses the CD-SCSAG method that has replaced it. Other changes are that

here curvilinear internal coordinates [COORD = curv2] are used here to calculate

bound-state vibrational frequencies and generalized normal modes, and that the run uses

SPECSTOP keyword. The curvilinear internal coordinates used for the O-H + H'-H" →

H-O-H' + H" hydrogen atom transfer reaction include the O-H, H'-H", and O-H' stretches,

the H-O-H' and H"-H'-O bends, and the H"-H'-O-H dihedral [INTDEF]. The MEP is

calculated from s = -1.0 bohr to s = 1.0 bohr [SRANGE] or until the VaG curve goes below

95% from its value at the saddle point to its value at the reactants [SPECSTOP]. The MEP

is determined using the Page-McIver method [RPM = pagem] with the cubic starting

algorithm [FIRSTSTEP = cubic]. The gradient and save step sizes are both set to 0.062

bohr [SSTEP, INH = 1]. The CVT/MEPSAG and CVT/CD-SCSAG rate constants are

calculated [CVT, ZCT, SCT] at 200K and 300K [TEMP].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3tr8.dat poly.fu5 input data file

oh3tr8.fu6 poly.fu6 long output file

oh3tr8.fu14 poly.fu14 summary output file

oh3tr8.fu15 poly.fu15 summary output file

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Polyrate 404

16.C.72. Test run oh3tr9

OH + H2 → H2 + H VTST calculation including a well on the reactant side and

writing a fu31 file

This sample test run writes the fu31 input file from the information calculated using an

analytical potential energy surface. The run does not require any fu31 input file and the

resulting fu31 file is ready to be used without any change. In addition, a well that is 1.28

kcal/mol more stable than the reactants is optimized, and its frequencies are calculated.

The data is written to the fu31 file.

The vibrational analysis is carried out in curvilinear coordinates, and debugging

information on this analysis is printed out to the fu6 output file.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch5fu31tr1.dat poly.fu5 input data file

ch5fu31tr1.fu31 poly.fu31 input data file

ch5fu31tr1.fu50 poly.fu50 input data file

ch5fu31tr1.fu6 poly.fu6 long output file

ch5fu31tr1.fu15 poly.fu15 summary output file

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Polyrate 405

16.C.73. Test run oh3tr10

OH + H2 → H2O + H with harmonic approximation and an ESD/RODS reaction

path

This sample run uses the WRITEFU31 keyword to generate an fu31 file, and it uses the

RODS keyword to make up for deficiencies in the path. All normal modes and generalized

normal modes are treated using the default harmonic approximation. The ESD integrator

[RPM = esd] with a step size of 0.05 bohr [SSTEP] is used to follow the MEP, and the

RODS algorithm [RODS] is used to correct the energies and frequencies along the path.

The Hessian matrix is recalculated and a generalized normal mode analysis is performed

every 0.05 bohr [INH = 1].

MEPSAG tunneling corrections [ZCT] are computed, and CVT [CVT] rate constants are

calculated at eight temperatures [TEMP]. The derivative of the gradient with respect to the

reaction coordinate is found by a quadratic fit [CURV = dgrad].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3tr10.dat poly.fu5 input data file

oh3tr10.fu6 poly.fu6 long output file

oh3tr10.fu14 poly.fu14 summary output file

oh3tr10.fu15 poly.fu15 summary output file

oh3tr10.fu31 poly.fu31 input data file

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Polyrate 406

16.C.74. Test run oh3fu30tr1

OH + H2 → H2O + H using electronic structure input file data from file fu30 and

curvilinear internal coordinates

This sample run demonstrates the use of electronic structure input file data in the

calculation of conventional TST rate constants [POTENTIAL = unit30] for the reaction

OH + H2 → H2O + H. Hessians are read in packed format in mass-scaled coordinates

[LOPT(4) = -2 in unit fu30 input]. Note that even though the reaction path is not required

for a conventional TST rate constant calculation, the PATH section must be included in the

unit fu5 input in order to pass to the program the value of the factor used in scaling the

coordinates [SCALEMASS in the unit fu5 input], and the data for at least two points along

the reaction path have to be input from unit fu30. The curvilinear internal coordinates

[COORD = curv2] used for the O-H + H'-H" → H-O-H' + H" hydrogen atom transfer

reaction include the O-H, H'-H", and O-H' stretches, the H-O-H' and H"-H'-O bends, and

the H"-H'-O-H dihedral [INTDEF]. All normal modes are treated harmonically

[HARMONIC in the unit fu5 input].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3fu30tr1.dat poly.fu5 input data file

oh3fu30tr1.fu30 poly.fu30 input data file

oh3fu30tr1.fu6 poly.fu6 long output file

oh3fu30tr1.fu14 poly.fu14 summary output file

oh3fu30tr1.fu15 poly.fu15 summary output file

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Polyrate 407

16.C.75. Test run oh3fu30tr2

OH + H2 → H2O + H using electronic structure input file data from file fu30 and

curvilinear internal coordinates

This sample run demonstrates the use of electronic structure input file data in the

calculation of rate constants [POTENTIAL = unit30] for the reaction OH + H2 → H2O +

H. This type of calculation requires the unit fu30 input file. The normal mode and

generalized normal mode frequencies are obtained at each save point on the MEP by first

transforming the Cartesian Hessian matrix into curvilinear internal coordinate space,

projecting out the gradient direction, and then diagonalizing the projected Hessian using

the Wilson GF method. The curvilinear internal coordinates [COORD = curv2] used for

the O-H + H'-H" → H-O-H' + H" hydrogen atom transfer reaction include the O-H,

H'-H", and O-H' stretches, the H-O-H' and H"-H'-O bends, and the H"-H'-O-H dihedral

[INTDEF]. The curvature components are computed using a quadratic fit to obtain the

derivative of the gradient with respect to the reaction coordinate [LOPT(6) = 4]. All

normal modes and generalized normal modes are treated harmonically [HARMONIC in the

unit fu5 input], and only TST and CVT rate constants are calculated [CVT] at four

temperatures [TEMP], using both MEPSAG and CD-SCSAG tunneling corrections [ZCT,

SCT].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3fu30tr2.dat poly.fu5 input data file

oh3fu30tr2.fu30 poly.fu30 electronic structure

input file data

oh3fu30tr2.fu6 poly.fu6 long output file

oh3fu30tr2.fu14 poly.fu14 summary output file

oh3fu30tr2.fu15 poly.fu15 summary output file

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Polyrate 408

16.C.76. Test run oh3fu30tr3

OH + H2 → H2O + H direct dynamics calculation using the electronic structure data

read from file fu30, rectilinear coordinates, and IVTST-M-4/4

interpolation.

This sample run demonstrates the use of electronic structure input file data read from unit

fu30 in the calculation of rate constants [POTENTIAL = unit30] for the reaction OH +

H2 → H2O + H. This type of calculation requires the unit fu30 input file. The

interpolation is done using IVTST-M-4/4 [LOPT(2) = 500]. Note that the normal mode

and generalized normal mode frequencies are obtained by diagonalization of the matrix

of the second derivatives of the potential with respect to the mass-scaled Cartesian

coordinates, which is read in packed form from unit fu30 [LOPT(4) = -2 in the unit fu30

input], and no anharmonic data are included [LOPT(5) = 0]. All normal modes are treated

harmonically [HARMONIC in the unit fu5 input], and only TST and CVT rate constants are

calculated [CVT] at four temperatures [TEMP], using both MEPSAG and CD-SCSAG

tunneling corrections [ZCT, SCT].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3fu30tr3.dat poly.fu5 input data file

oh3fu30tr3.fu30 poly.fu30 input data file

oh3fu30tr3.fu6 poly.fu6 long output file

oh3fu30tr3.fu14 poly.fu14 summary output file

oh3fu30tr3.fu15 poly.fu15 summary output file

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Polyrate 409

16.C.77. Test run oh3fu30tr4

OH + H2 → H2O + H using electronic structure input file data from file fu30 for

generating the next point along the reaction path (reactants

valley).

This sample run demonstrates the use of the NEXTPT keyword for generating the next

point along the reaction path in conjunction with the use of electronic structure input

from file fu30 [POTENTIAL = unit30] for the reaction OH + H2 → H2O + H. Note that

the print option LOPT(1) and IFITV are set equal to 0 in file fu30 because nonzero values

for these variables are incompatible with NEXTPT. Electronic structure information is

included for two points on the reaction path (one on each side of the saddle point), with

the first one having a positive s and the second one having a negative s (thus the points

are not in increasing order of s, but this is permitted when NEXTPT is on). Since the last

point has a negative s, IDIRECT is set equal to -1. The next point is generated on the

reactants side using a step size of 0.0005 amu1/2 bohr [SSTEP].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3fu30tr4.dat poly.fu5 input data file

oh3fu30tr4.fu30 poly.fu30 input data file

oh3fu30tr4.fu6 poly.fu6 long output file

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Polyrate 410

16.C.78. Test run oh3fu30tr5

OH + H2 → H2O + H using electronic structure input file data from file fu30 for

generating the next point along the reaction path (products

valley).

This sample run demonstrates the use of the NEXTPT keyword for generating the next

point along the reaction path in conjunction with the use of electronic structure input

from file fu30 [POTENTIAL = unit30] for the reaction OH + H2 → H2O + H. Note that

the print option LOPT(1) and IFITV are set equal to 0 in file fu30 because nonzero values

for these variables are incompatible with NEXTPT. Electronic structure information is

included for two points on the reaction path (one on each side of the saddle point), with

the last one being in the products valley. Since the last point has a positive s, IDIRECT is

+1. The next point is generated on the products side using a step size of 0.0005 amu1/2

bohr [SSTEP].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3fu30tr5.dat poly.fu5 input data file

oh3fu30tr5.fu30 poly.fu30 input data file

oh3fu30tr5.fu6 poly.fu6 long output file

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Polyrate 411

16.C.79. Test run oh3fu30tr6

OH + H2 → H2 + H fu30 calculation including a well on the reactant side

The oh3fu30tr6 test run is a sample run that uses file fu30 and includes a well on the

reactant side in the calculation. The reaction path is interpolated by means of third order

Lagrangian interpolation using the points along the reaction path including the reactant

well. The file fu30 was created with the writefu30 option, with only two changes being

necessary: to input of the value of the reaction coordinate, s, at the reactants well, and to

reorder of the points.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3fu30tr6.dat poly.fu5 input data file

oh3fu30tr6.fu30 poly.fu30 input data file

oh3fu30tr6.fu6 poly.fu6 long output file

oh3fu30tr6.fu14 poly.fu14 summary output file

oh3fu30tr6.fu15 poly.fu15 summary output file

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Polyrate 412

16.C.80. Test run oh3fu31tr1

OH + H2 → H2 + H IVTST-M calculation including a well on the reactant side

This sample test run uses the unit31 option to perform an IVTST-M calculation

including a well on the reactant side. This is an IVTST-M-100/2002 calculation based on

an fu31 input file identical to the one written in the oh3tr9 test run. The value for the

step-size SINCW is set to 0.001 bohr, which is the step-size used in the generation of the

fu31 file.

Note that this run cannot be done without interpolating to the well, since the energies

given in the fu31 input file for some of the points on the reactant side are below the

energy of the infinitely separated reactants. Since the interpolation to two separated

products is based on a Eckart potential, which does not allow the presence of wells, the

algorithm would fail. Thus, the well is required in the present IVTST-M calculation. If

the information given on the reactant side of the reaction path were to be reduced to the

point where no energy lower than the reactant energy appears in the fu31 file, the

interpolation could be carried out using the reactant information.

The calculated reaction path is extended up to s = –1.70 a0 (using a scaling mass of

1.802023 a.u.). Since the well is estimated to be located at s = –1.73 a0, extending the

range of values of s further toward reactants could cause numerical errors, since the

reaction path has not been interpolated beyond the well. In general, whenever a finite

range of s is used in a IVTST-M calculation (i.e., reactions with only one reactant or only

one product, or reactions with wells), the user should check that the range of s given in

the fu5 file does not goes beyond the values of s estimated for the stationary point (or

points).

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3fu31tr1.dat poly.fu5 input data file

oh3fu31tr1.fu31 poly.fu31 input data file

oh3fu31tr1.fu6 poly.fu6 long output file

oh3fu31tr1.fu15 poly.fu15 summary output file

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Polyrate 413

16.C.81. Test run oh3fu31tr2

OH + DH → HOD + H direct dynamics calculation of an isotopically substituted

reaction using electronic structure data for the isotopically

unsubstituted reaction read from file fu31, using

ESD(H)/RODS, and using IVTST-M.

This sample run demonstrates how to use the OH + H2 → H2O + H reaction path along

with the ESD(H)/RODS [RODS] and IVTST-M algorithms and file fu31 [POTENTIAL =

unit31] to obtain the conventional TST, CVT, CVT/ZCT, and CVT/SCT rate constants

for the isotopically substituted reaction OH + DH → HOD + H. The ESD(H)/RODS

method is described in Ref. 50 in Sect. 21. The fu31 input file used in this run was

written using the WRITEFU31 option in a run on OH + H2 (not included in the test suite).

The KIES option must be included in the GENERAL section of file fu31 so that the correct

value of s is calculated for the isotopically substituted reaction.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3fu31tr2.dat poly.fu5 input data file

oh3fu31tr2.fu31 poly.fu31 input data file

oh3fu31tr2.fu6 poly.fu6 long output file

oh3fu31tr2.fu14 poly.fu14 summary output file

oh3fu31tr2.fu15 poly.fu15 summary output file

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Polyrate 414

16.C.82. Test run oh3fu40tr1

OH + H2 → H2O + H using electronic structure input file data from file fu40 and

curvilinear internal coordinates

This sample run demonstrates the use of electronic structure input file data in the

calculation of conventional TST rate constants [POTENTIAL = unit40] for the reaction

OH + H2 → H2O + H. Hessians are read in mass-scaled coordinates [HESSFORM =

msbohr, HESSUNIT = msbohr in file fu40]. Note that even though the reaction path is

not required for a conventional TST rate constant calculation, the PATH section must be

included in the unit fu5 input in order to pass to the program the value of the factor used

in scaling the coordinates [SCALEMASS in the unit fu5 input] and at least two points along

the reaction path have to be input from unit fu40. The curvilinear internal coordinates

[COORD = curv2] used for the O-H + H'-H" → H-O-H' + H" hydrogen atom transfer

reaction include the O-H, H'-H", and O-H' stretches, the H-O-H' and H"-H'-O bends, and

the H"-H'-O-H dihedral [INTDEF]. All normal modes are treated harmonically

[HARMONIC in the unit fu5 input].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3fu40tr1.dat poly.fu5 input data file

oh3fu40tr1.fu40 poly.fu40 input data file

oh3fu40tr1.fu6 poly.fu6 long output file

oh3fu40tr1.fu14 poly.fu14 summary output file

oh3fu40tr1.fu15 poly.fu15 summary output file

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Polyrate 415

16.C.83. Test run oh3fu40tr2

OH + H2 → H2O + H using electronic structure input file data from file fu40 and

curvilinear internal coordinates

This sample run demonstrates the use of electronic structure input file data in the

calculation of rate constants [POTENTIAL = unit40] for the reaction OH + H2 → H2O +

H. This type of calculation requires the unit fu40 input file. The normal mode and

generalized normal mode frequencies are obtained at each save point on the MEP by first

transforming the Cartesian Hessian matrix into curvilinear internal coordinate space,

projecting out the gradient direction, and then diagonalizing the projected Hessian using

the Wilson GF method. The curvilinear internal coordinates [COORD = curv2] used for

the O-H + H'-H" → H-O-H' + H" hydrogen atom transfer reaction include the O-H,

H'-H", and O-H' stretches, the H-O-H' and H"-H'-O bends, and the H"-H'-O-H dihedral

[INTDEF]. The curvature components are computed using a quadratic fit to obtain the

derivative of the gradient with respect to the reaction coordinate [CURVATURE =

compute and GRADDER = noextra in the unit fu40 input]. All normal modes and

generalized normal modes are treated harmonically [HARMONIC in the unit fu5 input], and

only TST and CVT rate constants are calculated [CVT] at four temperatures [TEMP], using

both MEPSAG and CD-SCSAG tunneling corrections [ZCT, SCT].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3fu40tr2.dat poly.fu5 input data file

oh3fu40tr2.fu40 poly.fu40 input data file

oh3fu40tr2.fu6 poly.fu6 long output file

oh3fu40tr2.fu14 poly.fu14 summary output file

oh3fu40tr2.fu15 poly.fu15 summary output file

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Polyrate 416

16.C.84. Test run oh3fu40tr3

OH + H2 → H2O + H direct dynamics calculation using the electronic structure data

read from file fu40, using rectilinear coordinates, and IVTST-M-

4/4.

This sample run demonstrates the use of electronic structure input file data read from unit

fu40 in the calculation of rate constants [POTENTIAL = unit40] for the reaction OH +

H2 → H2O + H. This type of calculation requires the unit fu40 input file. The

interpolation is calculated using IVTST-M-4/4 [MAXLPTS = 500]. Note that the normal

mode and generalized normal mode frequencies are obtained by diagonalization of the

matrix of the second derivatives of the potential with respect to the mass-scaled Cartesian

coordinates, which is read in packed form from unit fu40 [HESSFORM = packed,

HESSUNIT = msbohr], and no anharmonic data are included [ANHARM = none]. The

curvature components are computed using a quadratic fit to obtain the derivative of the

gradient with respect to the reaction coordinate [CURVATURE = compute, GRADDER =

noextra]. All normal modes are treated harmonically [HARMONIC in the unit fu5

input], and only TST and CVT rate constants are calculated [CVT] at four temperatures

[TEMP], using both MEPSAG and CD-SCSAG tunneling corrections [ZCT, SCT].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3fu40tr3.dat poly.fu5 input data file

oh3fu40tr3.fu40 poly.fu40 input data file

oh3fu40tr3.fu6 poly.fu6 long output file

oh3fu40tr3.fu14 poly.fu14 summary output file

oh3fu40tr3.fu15 poly.fu15 summary output file

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Polyrate 417

16.C.85. Test run oh3fu40tr4

OH + H2 → H2O + H using electronic structure input file data from file fu40 for

generating the next point along the reaction path (reactants

valley).

This sample run demonstrates the use of the NEXTPT keyword for generating the next

point along the reaction path in conjunction with the use of electronic structure input

from file fu40 [POTENTIAL = unit40] for the reaction OH + H2 → H2O + H. Electronic

structure information is included for two points on the reaction path (one on each side of

the saddle point), with the first one having a positive s and the second one having a

negative s (thus the points are not in increasing order of s, but this is permitted when

NEXTPT is on). Since the last point has a negative s, IDIRECT is set equal to -1. The next

point is generated on the reactants side using a step size of 0.0005 amu1/2 bohr [SSTEP].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3fu40tr4.dat poly.fu5 input data file

oh3fu40tr4.fu40 poly.fu40 input data file

oh3fu40tr4.fu6 poly.fu6 long output file

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Polyrate 418

16.C.86. Test run oh3fu40tr5

OH + H2 → H2O + H using electronic structure input file data from file fu40 for

generating the next point along the reaction path (products

valley)

This sample run demonstrates the use of the NEXTPT keyword for generating the next

point along the reaction path in conjunction with the use of electronic structure input

from file fu40 [POTENTIAL = unit40] for the reaction OH + H2 → H2O + H. Electronic

structure information is included for two points on the reaction path (one on each side of

the saddle point), with the last one being in the products valley. Since the last point has a

positive s, IDIRECT is +1. The next point is generated on the products side using a step

size of 0.0005 amu1/2 bohr [SSTEP].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3fu40tr5.dat poly.fu5 input data file

oh3fu40tr5.fu40 poly.fu40 input data file

oh3fu40tr5.fu6 poly.fu6 long output file

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Polyrate 419

16.C.87. Test run oh3fu40tr6

OH + H2 → H2 + H fu40 calculation including a well on the reactant side

The oh3fu40tr6 test run is a sample run that uses file fu40 and includes as the left-hand

edge of the interpolation interval a well on the reactant side in the calculation. The

reaction path is interpolated by means of third order Lagrangian interpolation using the

points along the reaction path including the reactants well.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

oh3fu40tr6.dat poly.fu5 input data file

oh3fu40tr6.fu40 poly.fu40 input data file

oh3fu40tr6.fu6 poly.fu6 long output file

oh3fu40tr6.fu14 poly.fu14 summary output file

oh3fu40tr6.fu15 poly.fu15 summary output file

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Polyrate 420

16.C.88. Test run hnitr1

H(a)/Ni(100) → H(a)/Ni(100) with harmonic approximation and ESD integrator

This sample run is for the surface diffusion reaction H(a)/Ni(100) → H(a)/Ni(100), where

both reactant and product are adsorbed species [PHASE = solid] on a fixed Ni lattice. In

this particular calculation none of the Ni atoms are allowed to move. All vibrational

modes are treated by the default harmonic approximation. Points along the MEP are

calculated by the Euler steepest-descents (ESD) integrator [RPM = esd] with a step size

of 0.0001 bohr [SSTEP], and a generalized normal mode analysis is performed every 0.02

bohr [INH = 200]. CVT rate constants [CVT] are calculated. In addition, MEPSAG and

CD-SCSAG transmission coefficients are included [ZCT, SCT]. The reaction path

curvature components are calculated using a quadratic fit to obtain the derivative of the

gradient with respect to the reaction coordinate [CURV = dgrad]. Note that the

electronic partition functions of the transition state and of the reactant are assumed to

cancel.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

hnitr1.dat poly.fu5 input data file

hnitr1.fu6 poly.fu6 long output file

hnitr1.fu14 poly.fu14 summary output file

hnitr1.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

pothni.dat UNIT = 4

FILE NAME = pothni.dat

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Polyrate 421

16.C.89. Test run h2nitr1

H2(a)/Ni(100) → 2H(a)/Ni(100) with harmonic approximation and ESD integrator

This sample run is for the unimolecular gas-solid-interface reaction H2(a)/Ni(100) →

2H(a)/Ni(100) where both reactant and products are adsorbed species [PHASE = solid] on

a fixed Ni lattice consisting of 817 Ni atoms. All vibrational modes are treated by the

default harmonic approximation. Points along the MEP are calculated by the ESD

integrator [RPM = esd] with a step size of 0.001 bohr [SSTEP], and a generalized normal

mode analysis is performed every 0.01 bohr [INH = 10]. CVT rate constants are

calculated [CVT] at 8 temperatures [TEMP]. In addition, MEPSAG, CD-SCSAG, and

LCG3 transmission coefficients are included [ZCT, SCT, LCTOPT], and only the ground

state is involved in the LCG3 exit arrangement for the LCG3 tunneling calculation

[NOALLEXCIT].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

h2nitr1.dat poly.fu5 input data file

h2nitr1.fu6 poly.fu6 long output file

h2nitr1.fu14 poly.fu14 summary output file

h2nitr1.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILES

poth2niads.dat UNIT = 4 FILE NAME = poth2niads.dat

poth2nilat.dat UNIT = 7 FILE NAME = poth2nilat.dat

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Polyrate 422

16.C.90. Test run ch4ohtr1

OH + CH4 → H2O + CH3 zero-order IVTST calculation

This sample run uses the ICOPT keyword [ICOPT: zero] for a zero-order IVTST (i.e.,

IVTST-0) calculation of the reaction OH + CH4 → H2O + CH3 at 19 temperatures

[TEMP]. The classical potential energy curve and the adiabatic ground-state energy curve

are approximated by Eckart functions from s = –2.0 bohr to s = 2.0 bohr [SRANGE]. The

Hessian grid spacing is set to 0.02 bohr [INH = 20]. The ab initio data taken from J.

Chem. Phys. 99, 1013 (1993) are input by means of the unit fu50 file. The ZCT keyword

is used since MEPSAG is the only semiclassical tunneling method available for the zero-

order IVTST calculation. The lowest-frequency vibrational mode of the generalized

transition state is treated as a hindered rotor [VANHAR, TOR], while all of the other modes

are treated by the default harmonic approximation.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch4ohtr1.dat poly.fu5 input data file

ch4ohic.dat poly.fu50 input data file

ch4ohtr1.fu6 poly.fu6 long output file

ch4ohtr1.fu14 poly.fu14 summary output file

ch4ohtr1.fu15 poly.fu15 summary output file

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Polyrate 423

16.C.91. Test run ch4ohtr2

OH + CH4 → H2O + CH3 zero-order IVTST calculation

This sample run uses the IVTST0 keyword for a zero-order IVTST (i.e., IVTST-0)

calculation of the reaction OH + CH4 → H2O + CH3 at 19 temperatures [TEMP]. The

classical potential energy curve and the adiabatic ground-state energy curve are

approximated by Eckart functions from s = -2.0 bohr to s = 2.0 bohr [SRANGE]. The

Hessian grid spacing is set to 0.02 bohr [INH = 20]. The ab initio data taken from J.

Chem. Phys. 99, 1013 (1993) are input by means of the unit fu29 file. The MEPSAG

method [ZCT] is the only semiclassical tunneling method available for the zero-order

IVTST calculation. All vibrational modes are treated by the default harmonic

approximation.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch4ohtr2.dat poly.fu5 input data file

ch4ohtr2.fu29 poly.fu29 input data file

ch4ohtr1.fu6 poly.fu6 output file

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Polyrate 424

16.C.92. Test run ch4ohtr3

OH + CH4 → H2O + CH3 zero-order IVTST calculation

This sample run uses the ICOPT keyword [ICOPT: zero] for a zero-order IVTST (i.e.,

IVTST-0) calculation of the reaction OH + CH4 → H2O + CH3 at 19 temperatures

[TEMP]. The classical potential energy curve and the adiabatic ground-state energy curve

are approximated by Eckart functions from s = –2.0 bohr to s = 2.0 bohr [SRANGE]. The

Hessian grid spacing is set to 0.02 bohr [INH = 20]. The ab initio data taken from J.

Chem. Phys. 99, 1013 (1993) are input by means of the unit fu50 file. The ZCT keyword

is used since MEPSAG is the only semiclassical tunneling method available for the zero-

order IVTST calculation. This sample run is the same as the ch4ohtr1 test run, except

that the lowest-frequency vibrational mode of the generalized transition state is treated as

a hindered rotor using the CO torsion option.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch4ohtr3.dat poly.fu5 input data file

ch4ohic.dat poly.fu50 input data file

ch4ohtr3.fu6 poly.fu6 long output file

ch4ohtr3.fu14 poly.fu14 summary output file

ch4ohtr3.fu15 poly.fu15 summary output file

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Polyrate 425

16.C.93. Test run ch4ohtr4

OH + CH4 → H2O + CH3 zero-order IVTST calculation

This sample run uses the ICOPT keyword [ICOPT: zero] for a zero-order IVTST (i.e.,

IVTST-0) calculation of the reaction OH + CH4 → H2O + CH3 at 19 temperatures

[TEMP]. The classical potential energy curve and the adiabatic ground-state energy curve

are approximated by Eckart functions from s = –2.0 bohr to s = 2.0 bohr [SRANGE]. The

Hessian grid spacing is set to 0.02 bohr [INH = 20]. The ab initio data taken from J.

Chem. Phys. 99, 1013 (1993) are input by means of the unit fu50 file. The ZCT keyword

is used since MEPSAG is the only semiclassical tunneling method available for the zero-

order IVTST calculation. This sample run is the same as the ch4ohtr1 test run, except that

the lowest-frequency vibrational mode of the generalized transition state is treated as a

hindered rotor using the CW torsion option.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch4ohtr4.dat poly.fu5 input data file

ch4ohic.dat poly.fu50 input data file

ch4ohtr4.fu6 poly.fu6 long output file

ch4ohtr4.fu14 poly.fu14 summary output file

ch4ohtr4.fu15 poly.fu15 summary output file

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Polyrate 426

16.C.94. Test run ch4cltr1

CH4 + Cl → HCl + CH3 zero-order IVTST calculation

This sample run uses the IVTST0 keyword for a zero-order IVTST (i.e., IVTST-0)

calculation of the reaction CH4 + Cl → HCl + CH3 at 4 temperatures [TEMP]. The

classical potential energy curve and the adiabatic ground-state energy curve are

approximated by Eckart functions from s = -1.0 bohr to s = 1.5 bohr [SRANGE]. The

Hessian grid spacing is set to 0.02 bohr [INH = 4]. The ab initio data are input by means

of the unit fu29 file. The MEPSAG method is the only semiclassical tunneling method

available for the zero-order IVTST calculation. All vibrational modes are treated by the

default harmonic approximation. The 2P3/2 and 3P1/2 states of Cl are used in the

calculation of the electronic partition functions [ELEC]. [This test run reproduces the

results of one of the test cases in Ref. 26 in Sect. 21.]

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch4cltr1.dat poly.fu5 input data file

ch4cltr1.fu29 poly.fu29 input data file

ch4cltr1.fu6 poly.fu6 output file

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Polyrate 427

16.C.95. Test run ch4cltr2

CH4 + Cl → HCl + CH3 first-order IVTST calculation

This sample run uses the IVTST1 keyword for a first-order IVTST (i.e., IVTST-1)

calculation of the reaction CH4 + Cl → HCl + CH3 at 4 temperatures [TEMP]. The

classical potential energy curve and the adiabatic ground-state energy curve are

approximated by Eckart functions from s = –1.0 bohr to s = 1.5 bohr [SRANGE]. The

Hessian grid spacing is set to 0.02 bohr [INH = 4]. The ab initio data are input by means

of the unit fu29 file. Both MEPSAG and SCSAG semiclassical tunneling methods [ZCT,

SCT] are used, since they are available for the first-order IVTST calculation. All

vibrational modes are treated by the default harmonic approximation. The 2P3/2 and 3P1/2

states of Cl are used in the calculation of the electronic partition functions[ELEC]. [This

test run reproduces the results of one of the test cases in Ref. 26 in Sect. 21.]

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch4cltr2.dat poly.fu5 input data file

ch4cltr2.fu29 poly.fu29 input data file

ch4cltr2.fu6 poly.fu6 output file

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Polyrate 428

16.C.96. Test run ch4otr1

CH4 + O → CH3 + OH CUS calculation using harmonic redundant curvilinear

coordinates

This sample run calculates canonical unified statistical model (CUS) rate constants

including MEPSAG, CD-SCSAG, LCG3, COMT, and OMT tunneling, based on the

information from an analytical potential energy surface. The reaction has two different

electronic states, but since they are very close in energy, they are assumed to be

represented by the same surface. Thus, the total rate constant should be multiplied by a

factor of 2 in order to take into account this electronic degeneracy. This is done by using

a factor of 6 for the saddle point electronic degeneracy instead of its value of 3.

The VaG(s) curve has two maxima near the saddle point. In order to estimate the

recrossing effects due to these maxima a CUS calculation is performed.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch4otr1.dat poly.fu5 input data file

ch4otr1.fu6 poly.fu6 long output file

ch4otr1.fu14 poly.fu14 summary output file

ch4otr1.fu15 poly.fu15 summary output file

POTENTIAL ENERGY SURFACE DATA FILE

potch4o.dat UNIT = 4

FILE NAME = potch4o.dat

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Polyrate 429

16.C.97. Test run ohcltr1

O + HCl → OH + Cl ICVT calculation using Morse 1 anharmonicity and internal

coordinates

This sample run calculates improved canonical variational theory (ICVT) rate constants

including MEPSAG and CD-SCSAG tunneling, based on the information from an

analytical potential energy surface. The saddle point and generalized transition states are

nonlinear [SPECIES = nonlints]. Internal coordinates are defined [INTDEF keyword]

as the OH (1-2) and HCl (2-3) bond lengths and OHCl (1-2-3) bond angle. Vibrational

modes are treated by the Morse I approximation [MORSE, MORMODEL = morsei], with a

dissociation energy [DEMIN] of 0.16968172 Eh.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ohcltr1.dat poly.fu5 input data file

ohcltr1.fu6 poly.fu6 long output file

ohcltr1.fu14 poly.fu14 summary output file

ohcltr1.fu15 poly.fu15 summary output file

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Polyrate 430

16.C.98. Test run ohcltr2

O + HCl → OH + Cl ICVT calculation using WKB-on-the-true-potential for

ground-state energies and Morse 1 anharmonicity for

excited stateenergies.

This sample run is the same as ohcltr1, except that the ground-state vibrational energy

levels are calculated using the WKB method on the true potential. All excited state

energy levels are computed using the Morse I approximation [MORSE, MORMODEL =

morsei], with a dissociation energy [DEMIN] of 0.16968172 Eh.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ohcltr2.dat poly.fu5 input data file

ohcltr2.fu6 poly.fu6 long output file

ohcltr2.fu14 poly.fu14 summary output file

ohcltr2.fu15 poly.fu15 summary output file

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Polyrate 431

16.C.99. Test run ohcltr3

O + HCl(v=1) → OH + Cl Adiabatic excited-state calculation using WKB-on-the-true-

potential for the v=1 stretch energy and for the ground-state

bend energy and Morse 1 anharmonicity for excited

statebend energies.

This sample run is the same as ohcltr2, except that the reaction is for excited-state stretch

vibration. The stretch vibration is treated as adiabatic along the full reaction path

[STATE adiab] with quantum number v=1 specified using the STATEOPT keyword.

The excited-state energy level for the stretch vibration and the ground-state vibrational

energy level for the bend vibration are calculated using the WKB method on the true

potential. Bend excited state energy levels are computed using the Morse I

approximation [MORSE, MORMODEL = morsei], with a dissociation energy [DEMIN] of

0.16968172 Eh. The ICVT calculation is limited to –1.5 a0 < s < 1.0 a0.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ohcltr3.dat poly.fu5 input data file

ohcltr3.fu6 poly.fu6 long output file

ohcltr3.fu14 poly.fu14 summary output file

ohcltr3.fu15 poly.fu15 summary output file

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Polyrate 432

16.C.100. Test run ohcltr4

O + HCl(v=1) → OH + Cl Partial-reaction-path (PRP) adiabatic excited-state

calculation using WKB-on-the-true-potential for stretch

energy and for the ground-state bend energy and Morse 1

anharmonicity for excited statebend energies.

This sample run is the same as ohcltr3, except that stretch vibraton is treated as adiabatic

in the v=1 state along the reaction path only up to s = –0.22 a0 and then in the ground

state for s>-0.22 a0. This is specified using the STATE diab keyword and specifying

transition state mode 2 in the first excited state before the diabatic switch and in the

ground excited state after the diabatic switch. Thermal treatment of the bend vibration

before and after the switch is explicitly indicated in the input. The energy level for the

stretch vibration and the ground-state vibrational energy level for the bend vibration are

calculated using the WKB method on the true potential. Bend excited state energy levels

are computed using the Morse I approximation [MORSE, MORMODEL = morsei], with a

dissociation energy [DEMIN] of 0.16968172 Eh. The ICVT calculation is limited to –1.5

a0 < s < 1.0 a0.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ohcltr4.dat poly.fu5 input data file

ohcltr4.fu6 poly.fu6 long output file

ohcltr4.fu14 poly.fu14 summary output file

ohcltr4.fu15 poly.fu15 summary output file

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16.C.101. Test run ohcltr5

O + HCl → OH + Cl ICVT and MUCVT calculation using Morse 1

anharmonicity and internal coordinates

This sample run is the same as ohcltr1, except that microcanonical variational theory

(MUCVT) rate constants are also calculated. The primary and secondary fits use 1-point

and 3-point fitting [MUVTOPT, FIT= GAS13].

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ohcltr5.dat poly.fu5 input data file

ohcltr5.fu6 poly.fu6 long output file

ohcltr5.fu14 poly.fu14 summary output file

ohcltr5.fu15 poly.fu15 summary output file

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16.C.102. Test run ch3tr1

CH + H2 → CH3 VRC-VTST calculation

This sample run calculates the variable reaction coordinate variational transition state

theory rate constants by canonical variational theory, microcanonical variational theory,

and total energy and angular momentum resolved microcanonical variational theory. One

pivot point is assigned to each reactant. Pivot point for CH is assigned as the C atom, and

pivot point for H2 is the center of mass of H2. The range of reaction coordinate s is [1.3,

6.5] Å with a step size 0.2 Å. The number of Monte Carlo samples (keyword NMC) is set

to 100 for each dividing surface. Note that this number should be set to around 1000 in a

production run in order to have a much lower uncertainty of the Monte Carlo integration.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

ch3tr1.dat poly.fu5 input data file

ch3tr1.fu6 poly.fu6 long output file

ch3tr1.fu15 poly.fu15 summary output file

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16.C.103. Test run h3o2fu31tr1

H2O2 + H → H2O + OH TST with torsional treatment for H2O2 using the

segmented-reference Pitzer-Gwinn (SRPG) method

This sample run calculates rate constants by conventional TST. This run is used to show

the usage of the SRPG method for treating a torsion. The potential energy surface is

provided by the h3o2fu31tr1.fu31 file.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

h3o2fu31tr1.dat poly.fu5 input data file

h3o2fu31tr1.fu31 poly.fu31 input data file

h3o2fu31tr1.fu6 poly.fu6 long output file

h3o2fu31tr1.fu15 poly.fu15 summary output file

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16.C.104. Test run h3o2fu31tr2

H2O2 + H → H2O + OH TST with torsional treatment for H2O2 using the

segmented-reference Alyala-Schlegel (SAS)

method

This sample run calculates rate constants by conventional TST. This run is used to show

the usage of the SAS method for treating a torsion. The potential energy surface is

provided by the h3o2fu31tr2.fu31 file.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

h3o2fu31tr2.dat poly.fu5 input data file

h3o2fu31tr2.fu31 poly.fu31 input data file

h3o2fu31tr2.fu6 poly.fu6 long output file

h3o2fu31tr2.fu15 poly.fu15 summary output file

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16.C.105. Test run h3o2fu31tr3

H2O2 + H → H2O + OH TST with torsional treatment for H2O2 using the

reference Pitzer-Gwinn (RPG) method

This sample run calculates rate constants by conventional TST. This run is used to show

the usage of the RPG method for treating a torsion. The potential energy surface is

provided by the h3o2fu31tr3.fu31 file.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

h3o2fu31tr3.dat poly.fu5 input data file

h3o2fu31tr3.fu31 poly.fu31 input data file

h3o2fu31tr3.fu6 poly.fu6 long output file

h3o2fu31tr3.fu15 poly.fu15 summary output file

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16.C.106. Test run h3o2fu31tr4

H2O2 + H → H2O + OH TST with torsional treatment for H2O2 using the

Alyala-Schlegel (AS) method

This sample run calculates rate constants by conventional TST. This run is used to show

the usage of the AS method for treating a torsion. The potential energy surface is

provided by the h3o2fu31tr4.fu31 file.

Polyrate I/O FILES

FILE NAME Polyrate FILE NAME

h3o2fu31tr4.dat poly.fu5 input data file

h3o2fu31tr4.fu31 poly.fu31 input data file

h3o2fu31tr4.fu6 poly.fu6 long output file

h3o2fu31tr4.fu15 poly.fu15 summary output file

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16.D. Summary of test runs

This section contains a summary of the test runs which make up the Polyrate test suite.

Analytic potential

ch5j1tr1 ch5j1tr2 ch5j1tr3 ch5j1tr4 ch5j1tr5 ch5j1tr6

ch5j1tr7 ch5j1tr8 ch5j1tr9 ch5j1tr10 ch5j1tr11 ch5j1tr12

ch5j2tr1 ch5j2tr2 ch5j2tr3 clhbrtr1 clhbrtr2 clhbrtr3

clhbrtr4 clhbrtr5 cmctr1 cwmctr1 cwmctr2 cwmctr3

h3tr1 h3tr2 h3tr3 h3tr4 ho2tr1 ho2tr2

ho2tr3 ho2tr4 oh3tr1 oh3tr2 oh3tr3 oh3tr4

oh3tr5 oh3tr6 oh3tr7 oh3tr8 oh3tr9 oh3tr10

hnitr1 h2nitr1 ch4otr1 cmctr3 ch5fu51tr1 nh3tr2

ohcltr1 ohcltr2 ohcltr3 ohcltr4 ohcltr5 ch3tr1

fu30

ch5fu30tr1 ch5fu30tr2 ch5fu30tr3 ch5fu30tr4 ch5fu30tr5 ch5fu30tr6

oh3fu30tr1 oh3fu30tr2 oh3fu30tr3 oh3fu30tr4 oh3fu30tr5 oh3fu30tr6

fu31

ch5fu31tr1 oh3fu31tr2 ohfu31tr1 h3o2fu31tr1 h3o2fu31tr2 h3o2fu31tr3

h3o2fu31tr4

fu40

ch5fu40tr1 ch5fu40tr2 ch5fu40tr3 ch5fu40tr4 ch5fu40tr5 ch5fu40tr6

oh3fu40tr1 oh3fu40tr2 oh3fu40tr3 oh3fu40tr4 oh3fu40tr5 oh3fu40tr6

IVTST-0 with fu29

ch5j2itr1 ch5fu29tr1 ch5fu29tr2 ch4ohtr2 ch4cltr1

IVTST-0 with fu50

ch5fu50tr1 ch4ohtr1

IVTST-1 with fu29

ch5j2itr2 ch4cltr2

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VTST-IOC with analytic potential and fu50

ch5fu50tr2 ch5fu50tr3 cmctr2 ho2tr5 nh3tr1

VTST-IOC with fu30, fu31, or fu40 and fu50

ch5icfu30tr1 ch5icfu30tr2 ch5icfu31tr1 ch5icfu40tr1 ch5icfu40tr2

VTST-ISPE with fu30, fu31, or fu40 and fu51

ch5fu51tr1 cmctr3

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17. DESCRIPTION OF FILES IN RELEASE OF VERSION 17

The source code is partitioned into 33 FORTRAN files. Note that a full Polyrate source

consists of everything in the 33 FORTRAN files that including modules and parameters.

A description of each Polyrate subprogram is given in Subsection 17.A.1. Subsection

17.A.2 briefly describes the subprograms SETUP and SURF, which must be supplied by the

user for runs that do not use any of the potentials provided for the test run suite. (Dummy

versions that can be used for runs with POTENTIAL = unit30, unit31, or unit40 are

in dumpot.f.) The input and output files for the sample runs are explained in Subsection

16.C. The Unix C shell scripts are explained in Subsection 15.A and Section 18. A list

of all the files in the distribution package can be found in Subsection 15.A.

The files polymq.F and polysz.F contain subprogram MXLNEQ for solving and inverting

sets of simultaneous linear equations and EISPACK subroutines for determining matrix

eigenvalues and eigenvectors. In the distributed version the machine precision variable

MACHEP is set equal to 1.0 1038 in the MXLNEQ subprogram and to 2-46 in the EISPACK

subprograms. We found these settings to be adequate for all machines on which we

tested the code.

If you received the Polyrate distribution in a tar format, then the files will automatically

be distributed into the default Polyrate directories as described in Section 15, except that

this manual may be in a separate file (not tarred with everything else).

17.A. FORTRAN files and subprograms, MODULE files, and PES subroutines

Subsection 17.A.1 contains an alphabetical list and brief descriptions of all the

subprograms that make up the Polyrate program, Subsection 17.A.2 describes the

MODULE files and the user-supplied potential energy subprograms, and Subsection 17.A.3

describes the FORTRAN files.

17.A.1. Polyrate subprograms

In many cases a more detailed description and some relevant references are given as

comments at the beginning of the FORTRAN code for each subprogram. Note that

subroutines may be divided into two groups, POLYRATE-proper routines and hooks

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routines. Routines that start with a Y or have HOOK in the name are always part of the

hooks.

ABSORD

Order the lowest eigenvalues and eigenvectors according to absolute values.

ACALC

Dummy routine in place of the corresponding ACESRATE routine.

ACESET

Dummy routine in place of the corresponding ACESRATE routine.

AITKEN

Performs a Lagrangian interpolation of the effective reduced mass from the

reaction-path Hessian grid.

AITKF2

Checks the Aitken interpolation for "bad" values, i.e., interpolants that do not lie

within the original range of the data.

AITKNF

Performs Aitken interpolation.

ALFCT

Computes the logarithmic values of factorials of even integers used in the

calculation of the Bernoulli numbers.

ANCOEF

Computes the anharmonicity coefficients xij and the constant term (E0) from

dimensionless normal coordinate force constants evaluated previously by

subprogram GRADDR, and then calculates the vibrational ground-state energy

and fundamentals from the anharmonicity coefficients and the constant term.

ANGL

Function that calculates the angle i-j-k.

ANGLCS

Function that calculates the sine and cosine of the valence angle between two

difference Cartesian vectors.

ANGLV

Calculates the angle between two vectors.

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ANHARM

Computes anharmonicities for bound normal modes. The anharmonicity option is

selected by the anharmonicity keywords.

ANHDER

Computes the 3rd and 4th derivatives along the generalized normal modes.

ARMUEF

Calculates the argument of the exponential in equation 19 of Ref. 48 in Sect. 21

for the interpolation of the effective mass for CD-SCSAG tunneling.

ARMUEF1

Calculates CDSC for the extrapolated points in IVTST-M with the hooks.

ARRSM

Calculates the moment of inertia for the points along the reaction path given in

fu31 and reorders them according to the value of s.

ARRSV

Reorders the value of VMEP(s) given as input in fu31 according to s.

ASYMALP

Calculates the direction cosines for an asymmetric gyrator.

ASYMCAL

Prints the moment of inertia of a group of asymmetric gyrators.

ASYMENT

Calculates the moment of inertia of an asymmetric gyrator.

ASYMNZD

Sets up the calculation of moment of inertia of an asymmetric gyrator.

ASYMRMI

Calculates the moment of inertia of an asymmetric gyrator.

AVERJ

Calculate an integral over all possible orientation of the angular momentum

vector J with its length fixed in the evaluation of the number of available states.

BANGLE1

Calculates the Wilson B-matrix (R/X) for bending.

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BCALC

Calculates the curvature components and the total curvature for the small-

curvature semiclassical adiabatic tunneling calculations.

BCALCP

Calculates Page-McIver curvature factors BmF.

BCALC0

Calculates the small-curvature effective mass at the saddle point by linear

interpolation.

BTORSN

Calculates the Wilson B-matrix (R/X) for a torsion.

BMAT

Calculates the Wilson B-matrix, R/X, where R are the curvilinear internal

coordinate vectors and X are the Cartesian coordinate vectors.

BMAT1

Forms the Wilson B-matrix row corresponding to a linear stretch coordinate

between atom j and atom i. The input is in the form of difference Cartesians.

BMAT2

Forms the rows of the Wilson B-matrix corresponding to a bent triatomic.

BMAT5

Forms the Wilson B-matrix rows corresponding to degenerate linear bends. The

input is in the form of two difference Cartesians defining the linear triatomic. The

definitions of the bends are those of Hoy et al. (Mol. Phys. 24, 1265 (1972)).

BMAT5X

Forms the Wilson B-matrix rows corresponding to degenerate linear bends. The

input is in the form of two difference Cartesians defining the linear triatomic by

first determining a transformation matrix to rotate the coordinate system such that

the molecule lies along the Z axis.

BIMAT

Calculates the generalized inverse of the Wilson B-matrix.

BTEN1

Forms the Wilson B-matrix 2nd derivative elements for a bond-length curvilinear

internal coordinate in terms of its first derivatives and magnitudes of difference

Cartesians.

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BTEN2

Computes the bent triatomic 2nd derivative Wilson B-matrix elements.

BTEN5

Defines the 2nd derivative Wilson B-matrix elements for the degenerate linear

bend in terms of the difference Cartesian vectors that define its bonds.

BTEN5X

Defines the 2nd derivative Wilson B-matrix elements for the degenerate linear

bend in terms of the difference Cartesian vectors that define its bonds so that the

molecular frame has the linear bend along the Z axis.

BTENTR

Transforms the Wilson B-matrix elements from difference Cartesians to

Cartesians.

BTENS

Calculates the tensor (X/R•R2/X

2•X/R).

BOLTZ

Performs the Boltzmann average of the tunneling probability by a numerical

integration with respect to E.

BRENT

Implements Brent's line minimization method. See Ref. 14 in Sect. 22.

BRNULI

Computes Bernoulli numbers used in the calculation of the WKB phase integral

for a double-well potential.

CALCS

Computes the minimum distance between two geometries along the reaction path

measured as a straight line between them.

CALCUB

Calculates the coefficients for the cubic polynomial used in the IVTST-M interpolation of VMEP(s) for unimolecular reactions.

CASE

Function that takes a string of 80 characters and converts the upper case letters in

the string to lower case letters.

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CENTER

Translates the center of mass of the system to the origin. Also calculates the

determinant of the moment of inertia tensor, which is equal to the product of the

three principal moments of inertia, since they are the eigenvalues of this matrix.

CENTR1

Determines the relative index assignments for a linear triatomic system (i -j-k).

Atom i is placed in the center and the j-k assignments are made arbitrarily.

CENTRAL

Determines which atom is the central atom for a bent triatomic by using bond

lengths, and calculates the bond angle.

CFLOAT

Function that takes a character string that contains a floating point number and

converts it to a floating point number as defined by standard FORTRAN

conventions.

CHKFRE

Checks if any of the vibrational frequencies are zero or imaginary.

CHKUP

Retrieves 3rd-order dimensionless normal coordinate force constants needed for

calculating the vibrational ground-state energy and fundamentals for simple

perturbation theory calculations.

CLASS

Finds the recursion relation for various classes of orthogonal polynomials used to

find the nodes in Gaussian-type quadratures.

CMS

Calculates the center of mass of a subset of the system.

COG

Defines a cut-off Gaussian correction function.

COHBT1

Defines a cut-off hyperbolic tangent correction function.

COHBT2

Defines a cut-off hyperbolic tangent correction function.

COLSHF

Performs shifting of Hessian grid data in the storage arrays.

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CONOUT

Prints out the curvilinear internal coordinates.

CONV40

Converts the geometries, gradients, and Hessians to atomic units.

CORTRM

Calculates Coriolis constants.

COSINE

Modified cosine function.

CROSSPROD

Calculate cross product of two vectors.

CRVVEC

Computes the curvature vector when unit40 input is used.

CUBST

Evaluates quantities necessary for the cubic-starting algorithm.

CUBIC

Finds the real root of ax3+ bx2+ cx + d = 0 closest to a given x value.

CUBIC2

Finds all roots (real and complex) of ax3+ bx2+ cx + d = 0.

CUSSPL

Spline fits the GGT,0(s) curve and finds the maxima and minima along the curve

for a CUS calculation.

CVCOOR

Driver for the curvilinear internal coordinate bound-state analysis of non-linear

polyatomics.

DAXPY

BLAS routine calculates yx+c .

DATTIM

Calls system-dependent subroutines DATE and TIME and writes the current date

and time.

DEFALT

Sets the defaults for all the parameters and variables used in POLYRATE. The

defaults for each different section of input is set in a separate subprogram for

clarity.

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DEFENG

Sets the defaults for keywords used in the ENERGETICS section.

DEFGEN

Sets the defaults for keywords used in the GENERAL section.

DEFLT40

Determines if the needed fu40 keywords were read for the IOPth species. Default

values are assigned when necessary.

DEFOPT

Sets the defaults for keywords used in the OPTIMIZATION section.

DEFPAT

Sets the defaults for keywords used in the PATH section.

DEFRAT

Sets the defaults for keywords used in the RATE section.

DEFSEC

Sets the defaults for keywords used in the SECOND section.

DEFSTA

Sets the defaults for keywords used in the all the stationary point sections.

DEFTUN

Sets the defaults for keywords used in the TUNNEL section.

DERIV2

Calculates the Hessian matrix by using a quadratic fit to the potential energy

surface. Only the potential is used, not its first derivatives.

DERV

Calculates the curvature vector related to third derivatives for IVTST calculations.

DERV24

Computes the second derivatives of the potential by fitting the analytic first

derivatives to a fourth-order polynomial around the desired location and then

taking the derivative of this polynomial.

DERVAG

Evaluates the first derivative of an n-dimensional point by the two-point central

difference method.

DFGN31

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Set defaults for a fu31 file.

DGAMMA

Evaluates the gamma function of order n 3.

DGEDI

Computes the determinant and inverse of a matrix using the factors computed by

DGEFA.

DGEFA

Factors a double precision matrix by Gaussian elimination.

DIATOM

Computes the equilibrium properties for a diatomic reactant or product treated as

a Morse oscillator.

DIGISTR

Function that transform a three digits integer into a string with 3 characters.

DIST

Function that calculates an interatomic distance.

DPMPAR

A service routine for HYBRD1 that computes machine precision.

DOGLEG

A service routine for HYBRD1 that determines the convex combination x of the

Gauss-Newton and scaled gradient directions that minimizes (ax - b) in the least-

squares sense, subject to the restriction that the Euclidean norm of dx be at most

delta.

DOPNM

Calculates the steepest-descent path and the generalized normal modes along the

MEP.

DOREPR

Calculates the reactant and product properties.

DOREST

Prepares a restart calculation (i.e., reads data from unit fu1, etc.).

DORODS

Subroutine used to setup a RODS or VRP(ESD) calculation.

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DORPH

Prepares the potential energy routines and sets up the MEP interpolation

information for an electronic structure input file calculation.

DOSAFR

Calculates the saddle point frequencies.

DOSAGE

Calculates the saddle point geometry.

DDOT

BLAS routine computs the dot product of two vectors.

DOTPRD

Computes the dot product between two vectors.

DPR123

Computes the dot product between two vectors. First vector points from atom 2

to atom 1; second vector points from atom 2 to atom 3.

DPSWAP

Swaps two double precision numbers.

DSCAL

BLAS routine scales a vector by a constant.

DSWAP

BLAS routine interchanges two vectors.

EBND

Computes the energy of a level of a quadratic-quartic potential by the

perturbation-variation method of Truhlar.

ECKARS

Interpolates the classical potential curve (IOP = 1) or the ground-state vibrationally

adiabatic energy curve (IOP = 2).

ECKART

Defines an Eckart correction function.

ECKRT

Interpolates frequencies with an Eckart or a hyperbolic tangent function.

EHOOK

The driver for the energy routines in the modular version of POLYRATE.

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EFFBATH

Computes the solvent contribution for the nonequilibrium solvation

approximation.

EFMAIN

The driver for the eigenvector following algorithm.

EFPHES

Prints the Hessian matrix in eigenvector following algorithm.

EFORMD

Forms geometry step by eigenvector following algorithm.

EFOVLP

Determines the overlap of the geometry steps in the eigenvector following

algorithm.

ELLIP

Computes elliptic integrals of the first and second kinds.

ELRPH

Evaluates generalized normal mode frequencies along the MEP when electronic-

structure input is used [POTENTIAL = unit30 or unit40].

ENDRODS

Subroutine used to finish a RODS or VRP(ESD) calculation.

ENDSLP

TSPACK subroutine that estimates the first derivative at the edges of the spline-fit

interval to be used as the two extra conditions of the global spline under tension.

ENORM

Calculates the norm of a vector x.

ENROUT

Writes reaction energetics information to FORTRAN unit fu6.

EPARTI

Function that computes the electronic partition function for IVTST calculations.

EPART

Computes the electronic partition function.

ERF

Calculates the error function.

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EVIB

Calculates vibrational energy levels.

EWKB

Uses a Chebyshev quadrature to compute the primitive WKB approximation to

the energy of a vibrational level of a quadratic-quartic potential.

EXPND

Expands triangular matrix A to square matrix B.

EXTRAP

Provides simple exponential extrapolations to the asymptotic values of quantit ies

used in tunneling calculations.

EXTRP40

Sets the values for extrapolation when using unit fu40 input.

EXTRP

Fits a straight line to two points and carries out interpolations or extrapolations.

F1DI

Evaluates the function VALVAG for LINMNR.

F1DIM

Computes the one-dimensional energy for use in line minimization subroutines.

FACORD

Orders the force constants scaling factors according to the actual sequence of the

curvilinear internal coordinate when FCSCALE is used.

FCINPT

Closes all the input files used in READ5.

FCMEP

Closes all the input and output files used in the MEP calculation.

FCN

Calculates an Eckart or a hyperbolic tangent function to be passed into the non-

linear equation solver.

FCRATE

Closes all the input and output files used in the rate constant and the tunneling

calculations.

FCSCL

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Scales diagonal elements of the force constant matrix in curvilinear internal

coordinates by corresponding scaling factors when FCSCALE is used.

FDIAG

Diagonalizes the force constant matrix and, optionally, prints out generalized

normal mode information.

FDIAG2

Diagonalizes the Cartesian force constant matrix for Hessians from unit 29 input

and, optionally, prints out generalized normal mode information.

FDJAC1

A service routine for HYBRD1 that computes a forward-difference approximation

to the n x n Jacobian matrix associated with a specified problem of n functions in

n variables. If the Jacobian has a banded form, then function evaluations are saved

by only approximating the nonzero terms.

FICLSE

Closes a file given the status with which to close the file and the FORTRAN unit

number to which the file is linked.

FINDL

Calculates the value for the RPL keyword in a VTST-IC input file (fu50) from a

lower-level calculation.

FINDLV

Calculates the range parameter for an Eckart function.

FINOUT

Computes and prints out the final set of rate constants. Also obtains activation

energies and bottleneck properties and analyzes the ratio of transition state theory

results to those of canonical variational transition state theory.

FIOPEN

Opens all files needed for a given calculation except for the main input and the

main output files (i.e., the files linked to FORTRAN units fu5 and fu6).

FITMAX

Finds the maximum in the adiabatic potential curve and the generalized free

energy of activation curve using 3- and 5-point fits.

FITMX

Finds the maximum of function f with a 5-point fit.

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FIVFT

Computes a quartic fit through five points for IVTST.

FIVPT

Computes a quartic fit of F = ax4+ bx3+ cx 2+ dx + e to five points.

FORMA

Forms the generalized inverse of the B-matrix by the Pulay prescription.

FORMF

Forms the product ATFA, where A is the A-matrix and F is the Cartesian force

constant matrix.

FORMF2

Forms the second term of curvilinear internal force constant matrix.

FORMG

Forms the G matrix.

FORMBT

Forms one xyz-band of the transformation matrix from Cartesian coordinates to

difference Cartesians.

FRPRMN

Conjugate gradients minimization subroutine.

FRSORT

Sorts a set of frequencies into ascending or descending order.

GAUSQD

Calculates the weights and abscissa for N-point Gauss-Legendre quadrature.

GAUSSQ

Computes the nodes and weights for Gaussian-type quadrature.

GBSLVE

For a symmetric tridiagonal n n matrix A, this subroutine finds the component n

of the n-dimensional vector v such that Av = c, where c is a vector of all zeros

except for 1 in the n-th position.

GBTQL2

Finds the eigenvalues and the first components of the eigenvectors of an

asymmetric tridiagonal matrix by the implicit QL method.

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GEMM

Performs fast matrix multiplication. From the BLAS library.

GENSEC40

Reads and processes the GEN40 section of the unit fu40 input.

GETFRQ

Obtains vibrational frequencies in cm-1

and generalized eigenvectors.

GFDIAG

This routine effectively diagonalizes the unsymmetric GF-matrix, formed by

product of G and F. The method is given by Macintosh and Michaelian (Can. J.

Spectrosc. 24, 65 (1979)). Only symmetric matrices are diagonalized here. the

GF product is never explicitly formed.

GFDIA2

This routine effectively diagonalizes the unsymmetric, rectangular GF matrix by

generalized inverse G matrix method. The method is given in P. Pulay,; G.

Fogarasi, J. Chem. Phys. 1992, 96, 2856.

GHOOK

The driver for the first derivative routines in the modular version of POLYRATE.

GIVTST

Driver for zero- and first-order interpolated VTST (the global approach) as

described in J. Chem. Phys. 95, 8875 (1991).

GRAD

Evaluates derivatives along normal mode (or generalized normal mode)

directions.

GRADDR

Calculates 3rd- and 4th-order dimensionless normal coordinate force constants.

GSETA

Dummy routine in place of the corresponding ACESRATE routine.

GSETM

Geometry optimization calculations needed when Polyrate is used with MOPAC.

GSETP

Geometry optimization calculations needed when Polyrate is used with an

analytic surface.

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HBT

Calculates the hyperbolic tangent at sMEP.

HEADR

Prints out the program header.

HHOOK

The driver for the second derivative routines in the modular version of POLYRATE.

HINDRT

Calculates the moment of inertia for internal rotation.

HINDRT1

Calculates the moment of inertia for internal rotation of an asymmetric gyrator.

HQSC

Semiclassical solution of a harmonic-quartic potential.

HRPART

Calculates the partition functions using the hindered-internal-rotator

approximation.

HRSET

Setup calculation of hinder rotor partition function.

HVAL

TSPACK subroutine that evaluates a Hermite interpolatory tension spline at a

point.

HYBRD

A service routine for HYBRD1.

HYBRD1

Finds a zero of a system of n nonlinear functions in n variables by a modification

of the Powell hybrid method.

ICFDRP

Driver of the curvilinear internal coordinate bound-state analysis for reactants and

products.

ICFDIAG

Driver for the curvilinear internal coordinate bound-state analysis of triatomics.

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ICINT

Function that takes a character string which is really an integer and converts it to

an integer. Error checking that is not possible using ichar is done.

ICODAL

Function that translates a set of alphanumeric characters into an integer code.

ICOUTRP

Prints out the curvilinear internal coordinates for reactants and products.

ICSAVE

Copies frequencies and eigenvectors for bound modes from curvilinear internal

coordinate work spaces to the locations used by Cartesian coordinate procedures.

ICSVRP

Copies the bound-state analysis results from the curvilinear internal coordinate

work spaces to the locations used by Cartesian coordinate procedures.

IDAMAX

BLAS routine finds the index of element having maximum absolute value.

IMOM40

Computes the moment of inertia.

INTCOR

Defines the curvilinear internal coordinates for reactants and products by splitting

the global connectivies into subsets.

INTERSC

Finds out the intersection of two integer arrays.

INTF31

Subroutine that reorders the information on stationary points taken from fu31 and

puts it on the correspondent arrays.

INTRVL

TSPACK function that locates the interval in the input data for a spline fit that

contains a certain point.

INVRT

Inverts a one-dimensional array of size N.

INVRT2

Inverts a two-dimensional array of size N1, N2.

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INVRT3

Inverts a three-dimensional array of size N1, N2, N3.

INERTA

Calculates the moment of inertia for a linear molecule or a diatomic, or the

product of the moments of inertia for a non-linear molecule in au.

INITVRC

Initializes the array IATSV(I,J) for the generalized transition state in variable

reaction coordinate calculations because START section is not give in the fu5 file.

INITZE

Initializes some of the variables and arrays.

INTAB

Writes out a table of all the input parameters.

INTABS

Writes out a table of all the input parameters associated with the stationary point

sections.

INTEGR

Integration driver for the PATH subroutine.

INTEUL

Performs Euler steepest-descents integration.

INTFNC

Calculates and returns the negative of the normalized gradient for the path

integration.

INTPM

Page-McIver reaction path algorithm..

INTPM2

Computes s /t for the Page-McIver method.

INTRPL

Calls POLFIT to do polynomial interpolation for a given quantity.

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IRCX

Intrinsic-reaction-coordinate pathfinder, using the method of Schmidt, Gordon,

and Dupuis.

IRFTG0

Computes the information necessary for dealing with the frequencies, Hessians,

and curvature vectors for unit fu40 input.

IRPHZ

Does interpolations for the zero-order IVTST calculations.

IRPH

Does interpolations for the first-order IVTST calculations.

ISWAP

Swaps two integers.

IVTMA

Interpolates the exponent for calculating CDSC by IVTST-M through the hooks.

IVTMD

Calculates the extrapolated points with IVTST-M through the hooks.

IVTMH

Sets up the parameters required for IVTST-M through the hooks.

IVTST0

Calculates the classical (i.e., Born-Oppenheimer) potential energy curve and the

adiabatic ground-state potential energy curve along the reaction path in a zero-

order VTST-IOC calculation.

JACSCF

Computes all eigenvalues and eigenvectors by the Jacobi method.

KAPA

Calculates transmission coefficients for IVTST calculations.

KAPPAS

Calculates the transmission coefficients using the uniform semiclassical WKB

method (MEPSAG) and the small curvature method (SCSAG).

KAPVA

Calculates the tunneling corrections for a set of temperatures.

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KG1

Nodes and weights for Kronrod quadrature.

LCG34

Calculates the tunneling probabilities PLCG34 (E) by the LCG34 method.

LCGIT

Builds the grid for the 1D spline under tension.

LCGNAD

Defines the limit between adiabatic and nonadiabatic regions for the LCT3 and

LCT4 methods.

LCGRD

Builds a 2D rectangular grid from selected points of the PES.

LCGSRT

Sorts the uniformized LCG3 or LCG4 probabilities.

LCGTHE

Calculates the primitive tunneling amplitude Ttun˜ s 0 ,np( ) by integration over the

straight-line LCG3 or LCG4 tunneling path using both Gauss-Legendre

quadrature and the trapezoidal rule.

LCGTR

Transforms a point of the PES to a point of the 2D rectangular grid.

LCNORM

Calculates the generalized normal mode coordinates corresponding to the scaled

displacements along the LCG3 or LCG4 tunneling path. These coordinates are

needed for eq. (14) of Ref. 20 in Sect. 21.

LCNWTN

Performs a Newton root search to determine the s value corresponding to a point

along the LCG3 or LCG4 tunneling path, using eq. (22) of Ref. 20 in Sect. 21.

LCPATH

Calculates the mass-scaled Cartesian coordinates of the LCG3 or LCG4 tunneling

path as given in eq. (8) of Ref. 20 in Sect. 21.

LCPROB

Calculates the uniformized LCG3 probabilities from the primitive values

Pprim

LCG3E( ) using eq. (30) of Ref. 20 in Sect. 21.

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LCPROJ

Calculates the projections of the generalized normal mode coordinates onto the

LCG3 path using eq. (14) of Ref. 20 in Sect. 21.

LCSET

Sets up the LCG3 tunneling path and calculates the angle between the MEP and

the tunneling path [eq. (12) of Ref. 20 in Sect. 21] along with the vibrational

period of eq. (17) of Ref. 20 in Sect. 21.

LCSINT

Performs the numerical integration over tunneling termini along the reaction path

as given by eq. (9) of Ref. 20 in Sect. 21.

LCSTX

Sets up the tunneling path for excited final states and determines the highest

excited state involved in LCG3 calculations.

LCTP

Determines the ending terminus of the tunneling path for a given excited state of

the LCG3 exit arrangement and a given initiating terminus ˜ s 0 using the resonance

condition.

LCTV4

Searches for a LCT4 nonadiabatic region within a LCG3 adiabatic region.

LCVCOR

Calculates the effective potential for the nonadiabatic region in an LCG3

calculation as given in eq. (28) of Ref. 20 in Sect. 21.

LCVIB

Calculates the vibrational zero-point energies of eq. (5) of Ref. 20 in Sect. 21.

LCVMOD

Calculates the zero-point energy and potential for a given normal mode in an

LCG3 calculation.

LCXINT

Calculates the integrand in the phase integral along the adiabatic segments of an

LCG3 tunneling path.

LCXTAU

Calculates the vibrational period, , for LCG3 calculations as given by eqs. (17)

and (18) of Ref. 20 of Sect. 21.

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LCZCRT

Determines which region (adiabatic or nonadiabatic) a given point on an LCG3

tunneling path is in by using eqs. (23) and (24) of Ref. 20 in Sect. 21.

LIN

Solves a set of simultaneous linear equations.

LIN2

Solves two simultaneous linear equations in the matrix form Ax = b.

LININT

Does the linear interpolation.

LINMNR

Finds the minimum along a given direction.

LINMN

One-dimensional minimization search.

LOCATE

Determines the indices on the grid of reaction path coordinates corresponding to a

point on the LCG3 tunneling path determined by LCNWTN.

LOCS

Called by AITKF2 to locate the s value about which to center the interpolation

grid. The grid is centered about the closest point on the Hessian grid.

LOPT40

Translates the GEN40 input keywords to LOPT values.

LSAME

Service routine for GEMM.

LUDCMP

Performs an LU decomposition using an algorithm from W. H. Press, B. P.

Flannery, S. A. Teukolsky, and W. T. Vetterling, Numerical Recipes (Cambridge

University Press, Cambridge, 1986), p. 31.

LUBKSB

Service routine for LUDCMP.

MAIN

Driver for POLYRATE. The main input and output files (i.e., those files linked to

FORTRAN units fu5 and fu6) are opened in this subprogram.

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MATINV

Performs matrix inversion using LU decomposition routines.

MATX

A general-purpose matrix multiplication routine.

MEPINV

Stores the information saved as functions of the reaction coordinate in order of

increasing s by inverting the order of storage.

MEPOUT

Prints MEP information to the long output file, i.e., to unit fu6.

MEPSRT

Does a bubble sort of the MEP information in order of increasing s.

MNBRAK

Finds an interval which contains a minimum.

MOPEG

Dummy routine to disable the keyword MOPAC in POLYRATE.

MOPHES

Dummy routine to disable the keyword MOPAC in POLYRATE.

MOPOPT

Dummy routine to disable the keyword MOPAC in POLYRATE.

MOPSET

Dummy routine to disable the keyword MOPAC in POLYRATE.

MTINV2

Performs matrix inversion using singular value decomposition routines

MUCDSC

Computes the centrifugal-dominant small-curvature effective mass.

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MUSC

Computes the SCSAG effective mass.

MUSCCD

Computes the CD-SCSAG effective mass.

MXLNEQ

Solves a set of simultaneous linear equations in the matrix form Ax = b, and

evaluates the determinant of A.

NEARWC

computes the nearest reactant or product endpoint used in frequency interpolation .

NEWT

Does a Newton-Raphson search for a stationary point.

NEXTPT

Computes the next point on the MEP.

NORMOD

Computes generalized normal mode frequencies and directions.

NOROUT

Prints out generalized normal mode information.

NOST31

Processes the information about non-stationary points along the reaction path.

NSTATE

Calculates the total number of accessible states in LCG3 calculations that include

contributions from tunneling into excited states.

NUMFRQ

Calculates the number of internal vibrations.

OBTSRT

Compares two elements and stores the bigger one.

OHOOK

The driver for the geometry optimization routines in the modular version of

POLYRATE.

OPENFI

Opens a file given the unit number, the status, and the file name.

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OPT50

Checks for any conflicts in the options for the VTST-IOC calculations.

OPT50C

Checks for consistency between the VTST-IOC options chosen in the unit fu50

input.

OPTION

Checks for consistency between the options chosen in the unit fu5 input and

writes out information about the options selected.

ORDS31

Reorders the information stored on the array save31 containing all the information

given as an input in fu31.

OVRLP

Computes overlaps between old and new normal mode eigenvectors and warns if

a crossing has occurred.

PATH

Calculates the reaction path.

PHID

Computes the phi function needed for uniform semiclassical quantization of a

double-well potential.

PHSINT

Computes the phase integral for the WKB method.

PMOI

Calculate priccipal moment of inertia and their unit vector along the ith principal

axis for each reactant or complex of reactants

POLINT

Uses Neville's algorithm to interpolate a given quantity.

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POLYAT

Calculates the equilibrium properties of a linear or a nonlinear polyatomic

reactant or product.

PRCORD

Prints the bond lengths, bond angles, and dihedral angle along the reaction path.

PREGPT

Spline fits s, V, and I-1 for IVTST-M calculations carried out through the hooks.

PREP

The driver for all the preparation routines in the modular version of POLYRATE.

PREPJ

The driver for all the preparation routines needed by REACT1, REACT2, PROD1,

PROD2, START, and PATH. See Sect. 8.C.

PRMEP

Prints extra MEP information to units fu25-fu27.

PRNTBT

Prints the B-matrix stored in lower triangular form in clusters of 5 rows.

PRNTFC

Prints a lower triangular matrix (in clusters of 5 rows).

PROJTI

Forms the projection operator and calculates the projected Cartesian force

constant matrix for IVTST calculations.

PROJCT

Calculates the projected force constant matrix and normalized gradient.

PROJF

Forms the projection operator and projects out the gradient from the curvilinear

internal force constant matrix.

PRSQ

Prints out a square matrix.

PSAG

Locates points (translational turning points) where the energy is equal to the

adiabatic potential and then computes the imaginary-action integral.

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PSATP

Finds turning points on the adiabatic barrier.

PSATP2

Finds turning points on the adiabatic barrier.

PSATX

Finds turning points on the adiabatic barrier.

PSATX2

Finds turning points on the adiabatic barrier.

PTORS

Function that calculates the torsion angle i-j-k-l.

PTQVIB

Calculates vibrational partition functions by simple perturbation theory using the

ground-state energy and fundamentals. [See Ref. 23 in Sect. 21 for the equations

without Coriolis terms in E0 and see Ref. 35 in Sect. 22 for the Coriolis

contributions to E0.].

PTSEC40

Reads and processes the POINT40 sections in the unit fu40 input.

PYC1

TSPACK subroutine that employs a three-point quadratic interpolation method to

compute local derivative estimates associated with a set of data points. The

derivatives are chosen so that the Hermite interpolatory tension spline fulfils the

user selected end conditions.

PYC1P

TSPACK subroutine that employs a three-point quadratic interpolation method to

compute local derivative estimates associated with a set of data points. The

derivatives are chosen so that the Hermite interpolatory tension spline fulfils the

defaulted end conditions.

PYC2

TSPACK subroutine that solves a linear system for a set of first derivatives

associated with a Hermite interpolatory tension spline. The derivatives are chosen

so that the Hermite interpolatory tension spline fulfils the user selected end

conditions.

PYC2P

TSPACK subroutine that solves a linear system for a set of first derivatives

associated with a Hermite interpolatory tension spline. The derivatives are chosen

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so that the Hermite interpolatory tension spline fulfils the defaulted end

conditions.

PYCOEF

TSPACK subroutine that computes the coefficients of the derivatives in the

symmetric diagonally dominant tridiagonal system associated with the C-2

derivative estimation procedure for a Hermite interpolatory tension spline.

QFORM

Computes the QR factorization.

QQPOT

Fits the quadratic-quartic potential to two points along the generalized normal

coordinate using two given distances.

QRFAC

This is a service routine for HYBRD1 that uses Householder transformations with

column pivoting (optional) to compute a QR factorization of the m x n matrix A.

QRSENE

Calculates the quantized reactant eigenstates for tunneling.

QSLVE

Computes a quadratic fit to the function values at two points and the derivative at

one point, and uses the fit to perform an interpolation.

QTQVIB

Calculates the quantized reactant-state partition functions.

QUADFT

Computes a quadratic fit to three points.

QUADR

Solves a quadratic equation.

QUADTW

For a function y (x) = A + B (x–C)2, finds B and C from the given information.

RBASIS

Dummy routine in place of the corresponding ACESRATE routine.

RBATH

Reads the keyword options for the BATH keyword in PATH section.

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R1UPDT

A service routine for HYBRD1.

R1MPYQ

A service routine for HYBRD1.

RACES

Reads the ACES namelist options.

RALL31

Reads all the data from fu31 and store it in the save31 array.

RATE

Computes the generalized free energy of activation curves and rate constants.

RAN1

Random number generator from Numerical Recipes.

RANALY

Reads the temperatures at which a detailed analysis is desired.

RATOMS

Reads the atomic symbols and optionally the masses.

RCNST

Reads the coordinates that will be held constant in any optimization of a

stationary point geometry.

RD40EXTR

Reads the EXTRAP40 section of the file fu40 input.

RD40GEN

Reads the GEN40 section of the file fu40 input.

RD40RP

Reads the reactants and products sections of the file fu40 input.

RDETIL

Reads the LCG3 output details information.

RDIATM

Reads the diatomic options for stationary points.

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RDIFFU

Reads the diffusion coefficients or coupling constants for the nonequilibrium

solvation calculation.

RDHESS

Reads a Hessian matrix from file fu40.

RDLN

Reads a line from an input file without conversion.

REACT

Computes the geometry and properties of a reactant or product.

REACTCOM

Calculate center of mass for reactants

READ5

Reads input from the file linked to FORTRAN unit fu5.

READIC

Reads the VTST-IOC correction data from the file linked to FORTRAN unit

fu50.

READINT

Reads INTDEF keyword information to get the connectivities.

READLN

Reads a line from an input file and converts all characters to uppercase.

REARG1

Rearranges a set of frequencies to an order that is input by the user.

RECS31

Recalculates all the values of s given in fu31 as distances along straight lines

between two consecutive geometries.

REDGEO

Determines the geometry of the reactant, product, or saddle point, i.e., linear or

nonlinear, and the number of degrees of freedom.

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REDMU

Evaluates the effective mass for a given value of s for IVTST as described in J.

Chem. Phys. 95, 8875(1991).

REFOPT

Reads the options for eigenvector following algorithm.

RELEC

Reads the electronic degeneracies for stationary points.

RENERG

Reads the ENERGETICS section of the file fu5 input.

REPFL

Replaces the low-frequency mode along the path when the IVTST0FREQ keyword

is used.

RES1

Reads the variables for the Euler-with-stabilization (ES1) integrator.

RESTOR

Reads information from the file linked to FORTRAN unit fu1 for a restart rate

constant calculation.

RESTRT

Writes information to the file linked to FORTRAN unit fu1 for a restart rate

constant calculation.

REXTRP

Reads the EXTRAP section of the file fu5 input.

REZERO

Reads the input for the zero of energy.

REZERU

Reads the unit for the zero of energy.

RFCFAC

Reads FCSCALE keyword information to get the force constant scaling factors

when FCSCALE is used.

RFREQ

Reads frequencies from unit fu29 for IVTST calculations.

RGEM31

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Reads the options for geometry input in fu31.

RGEN

Reads general information for IVTST calculations from unit fu29.

RGEN31

Reads the options in the general section of an fu31 input file.

RGENER

Reads the GENERAL section of the file fu5 input.

RGEOM

Reads the initial geometry for reactants or products.

RGRD

Read gradient from unit fu29 for IVTST calculations.

RGRD31

Reads the options for gradients input in fu31.

RGSAD

Reads the initial geometry for the saddle point or starting geometry.

RGSPEC

Reads the range of s for which the generalized free energy curve is to be

computed.

RGSZM

Reads the initial geometry for the saddle point or starting geometry using z-matrix

form.

RGTEMP

Reads the range of s values for each temperature for which the generalized free

energy curve is to be computed.

RGZMAT

Reads the initial geometry for the saddle point or starting geometry using z-matrix

form. This is used only when the geometry optimization is done using ACES.

RHESS

Reads Hessians from unit fu29 for IVTST calculations.

RHES31

Reads a Hessian matrix from fu31.

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RHESSC

Reads HESSCAL options from unit fu5.

RHFSEC

Checks whether frequencies or Hessians are to be read.

RHSS31

Reads the options for Hessian input in fu31.

RICOPT

Reads the VTST-IOC options.

RLCT

Reads the information for large-curvature tunneling calculations.

RLINE

Utility program for reading a line of input and parsing off extra spaces and

comments.

RLOWFR

Reads the information given by the LOWFREQ keyword.

RMUVT

Reads VT options.

ROPT

Reads the OPTIMIZATION section of the file fu5 input.

ROPT31

Reads the general section of an incomplete fu31 file and sets the options for

writing it.

ROPTOP

Reads the options for the OPTIMIN and OPTTS keywords.

RPART

Computes the classical rotational partition function.

RPARTI

Computes the classical rotational partition function for IVTST calculations.

RPATH

Reads the PATH section of the file fu5 input.

RPH31

Sets up the defaults and routes for reading an fu31 file.

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RPH40

Sets up the electronic structure information from file fu40.

RPHAIT

Performs NINT-point Lagrangian interpolation of an asymptotic function used in

the electronic structure input file option (i.e., the RPH formulation).

RPHB

Calculates the curvature component of mode k.

RPHDXN

Converts from unweighted to mass-scaled gradient and normalizes the gradient

vector.

RPHEXP

Evaluates asymptotic exponential functional forms.

RPHFIT

Evaluates parameters of the asymptotic exponential fits.

RPHFT2

Computes 2-point fits to 3-parameter asymptotic exponential functions with the

range parameter fixed.

RPHFT3

Computes 3-point fits to 3-parameter asymptotic exponential functions.

RPHG1

Function used in the root search for the range parameter in an asymptotic

functional form.

RPHG2

Function used in the root search for the range parameter in an asymptotic

functional form.

RPHG5

Function used in the root search for the range parameter in an asymptotic

functional form.

RPHINT

Interpolates RPH information.

RPHMEF

Computes the effective tunneling mass for CD-SCSAG from the interpolated

value of the exponent in equation 19 in Ref. 48 in Sect. 21.

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RPIVOT

Reads the Cartesian coordinates of pivot points

RPNT31

Reads the information from each point in the fu31 file.

RPHNWT

Performs a Newton search for the zero of one of the functions G(C) defined in

Subsection 9.D.1.

RPHRD1

Reads electronic structure input information and sets up tables used for

interpolation.

RPHRD2

Reads electronic structure input information.

RPHSET

Sets up electronic structure input interpolation information.

RPHTRF

Transforms the matrix of second derivatives with respect to unweighted

coordinates to second derivatives with respect to mass-scaled coordinates.

RPHTRX

Converts mass-scaled to Cartesian coordinates or Cartesian to mass-scaled

coordinates.

RPHWRT

Writes reaction path Hamiltonian interpolation information.

RPOTET

Reads the potential type.

RPOTGE

Reads the potential type to be used for optimizing the geometry.

RPRFL

Replaces the low-frequency mode of the stationary points when the IVTST0FREQ

keyword is used.

RPRMEP

Reads the parameters for printing the extra MEP information.

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RPRVIB

Reads the range of s between which extra vibrational mode information and Qvib

are printed.

RPSEC40

Reads and processes a reactant or product section of the file fu40 input.

RQCOM

Calculates the distance between the centers of mass of two reacting species.

RQRST

Reads the information for the quantized-reactant-state tunneling calculation.

RQUAD

Reads the quadrature information for the tunneling calculations.

RRANGE

Reads the range of s values for which the reaction path is to be computed.

RRATE

Reads the RATE section of the file fu5 input.

RRPM

Reads the value of the RPM keyword of the file fu5.

RRSTRT

Reads the restart options.

RSCT

Reads the options for small curvature tunneling.

RSECND

Reads SECOND section of the file fu5 input.

RSFRST

Reads the variables for a special step size for the first n steps.

RSP

EISPACK diagonalization routine. Finds the eigenvalues and eigenvectors of a

real symmetric packed matrix.

RSPDRV

Accepts unpacked arrays the way EISPACK subroutine RS does, packs them for

RSPP, and calls RSPP to compute eigenvalues and eigenvectors.

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RSPECL

Reads special values of s at which a normal mode analysis is to be done.

RSPP

Diagonalizes a real symmetric matrix in packed form.

RSSTOP

Reads the options of the SPECSTOP keyword.

RST

Diagonalizes a real symmetric matrix using RSPP.

RSTAT

Reads all the stationary point sections of the file fu5 input.

RSTATE

Reads the options used with a state-selected rate constant calculation.

RSVRC

Reads the range and step size of variable reaction coordinate

RTEMP

Reads the temperatures at which the rate constant is to be calculated.

RTITLE

Reads the title.

RTOR

Reads the TOR keyword options.

RTOROPT

Reads the TOROPT keyword options.

RTPJAC

Prints the MEP and large curvature representative tunneling termini in mass-

scaled Jacobian coordinates.

RTUNNL

Reads the tunneling parameters.

RUNM31

Reads the options for the IVTST-M interpolation on a unimolecular side (or side

with a well) on the reaction path.

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RVAR6

Reads keyword values in a restart calculation.

RVARY

Reads the variable anharmonicity options desired for reactants, products and or

the saddle point.

RVPERT

Reads the options for using simple perturbation theory for the vibrational partition

functions.

RVRANG

Reads the anharmonicity options desired for the reaction path for specific regions

of the reaction coordinate s.

RVRCOPT

Reads the options for variable reaction coorindate calculations.

RWKB

Reads the WKB anharmonicity options.

RWORD

Parses a character string to find the next word.

RZVAR

Reads the z-matrix variables for the geometry optimization of the reactants,

products and the saddle point.

SADDLE

Computes the saddle point geometry (with subroutine NEWT) and other saddle

point properties.

SADENG

Computes the saddle point energetics.

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SADSEC40

Reads and processes the SADDLE40 section of the file fu40 input.

SAVEXRP

Calculate Cartesian coordinate of each reactant and the other pivot points relative

to the first pivot point of reactant 1.

SECCEN

Calculates second derivatives by the method of central differences.

SECCEP

Calculates second derivatives by the method of central differences; only computes

part of the Hessian matrix.

SENOUT

Writes saddle point energetics information to unit fu6.

SETANH

Sets variables associated with the variable anharmonicity option.

SETLGS

Converts the variables and flags set by evaluating the keywords to the

corresponding LGS flags.

SETUP

Called once to initialize the potential, as discussed in Sect. 8.C.1. Ordinarily, this

is supplied by the user. The distribution, however, contains a dummy version for

use as described in Section 8.C, as well as sample versions for the test runs.

SETVAR

Converts the variables and flags set by evaluating the keywords to the

corresponding Polyrate variables.

SGND3V

Stores the sign of the third derivative in an array for use in computing the Morse

turning point.

SHFTSAD

Shifts saddle point information when using unit fu40 input.

SIGS

TSPACK subroutine that determines the value of the tension factors for a spline

under tension fit.

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SIMPSN

Calculates the phase integral by using Simpson’s rule in the quantized-reactant-

state tunneling calculation.

SINE

Modified sine function.

SNHCSH

TSPACK subroutine that computes approximate values for modified hyperbolic

functions.

SORTG

Sorts frequencies in descending order.

SORT31

Sorts an nx2 array according to the values on the first column.

SPL1B1

Converts the spline fit data supplied by SPL1D1 to four arrays containing the

coefficients for local cubic fits.

SPL1B2

Computes the spline interpolation using the cubic polynomial coefficients

supplied by SPL1B1.

SPL1D1

Computes the second derivative array for spline interpolations.

SPL2D

Calls the 2D spline under tension.

SPL31

Subroutine that interfaces Polyrate and TSPACK. This subroutine is used when

the information is given by means of fu31, which allows for a different number of

data for each property.

SPLNB

Calculates the value of the curvature components at any point along the reaction

path by using spline under tension fitting.

SPLNF

Calculates the value of the frequencies at any point along the reaction path by

using spline under tension fitting.

SPLNM

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Calculates the value of the moment of inertia at any point along the reaction path

by using spline under tension fitting.

SPLNMF

Calculates the value of the effective mass for CD-SCSAG tunneling at any point

along the reaction path by using spline under tension fitting.

SPLNV

Calculates the value of the energy along the reaction path, VMEP(s) at any point

along the reaction path by using spline under tension fitting.

SPLM31

Calculates the value of the moment of inertia at any point along the reaction path

by using spline under tension fitting. This subroutine is used when the input is

given in fu31.

SPLRMI

Calculates the value of the moment of inertia at any point along the reaction path

by using spline under tension fitting.

SPLSPV

Spline fits V in the ISPE method. This subroutine is used with fu51.

SPLV31

Calculates the value of the energy along the reaction path, VMEP(s), at any point

along the reaction path by using spline under tension fitting. This subroutine is

used when the input is given in fu31.

SSAVE

Saves the reaction path results calculated in subroutine PATH.

SSX

Computes the distance between two Cartesian geometries as an straight line in

mass-scaled coordinates.

STAT31

Calculates stationary point properties from the information read in fu5 and fu31.

STAUV

Calculates the correction term used in computing the improved generalized

transition-state partition function from the generalized transition-state partition

function.

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STLGSJ

Converts the stationary-point-dependent variables and flags set by evaluating the

keywords to the corresponding LGS flags.

STOR

TSPACK subroutine that determines floating point number characteristics.

STVARJ

Converts the stationary-point-dependent variables and flags set by evaluating the

keywords to the corresponding Polyrate variables.

SURF

Evaluates the potential, as discussed in Subsection 8.C.1. Ordinarily this is

supplied by the user, but the Polyrate distribution provides a dummy version for

use as discussed in Section 8.C, as well as sample versions for the test runs.

SVBKSB

This routine, taken from Numerical Recipes, is for the backward substitution of

SV decomposition.

SVBCMP

This routine, taken from Numerical Recipes, is for the singular value

decomposition procedure.

TABLE

Writes a summary of selected forward rate constants to the file linked to

FORTRAN unit fu15.

TAUV

Calculates the cutoff partition function for improved canonical variational theory.

THETA2

Computes the phase integral for the semiclassical eigenvalues of a single-well

potential.

THETA3

Computes the phase integral for the semiclassical eigenvalues of a double-well

potential.

TITLE

Reads and writes the title of the job.

TP

Locates the turning points at a given energy for a normal mode vibration.

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TPCDSC

Calculates the centrifugal-dominant small-curvature turning point.

TQL2

Computes the eigenvalues and eigenvectors of a symmetric tridiagonal matrix by

the QL method [H. Bowdler, R. S. Martin, C. H. Reinsch, and J. H. Wilkinson,

Num. Math 11 (1968) 293].

TQLRAT

Finds the eigenvalues of a symmetric tridiagonal matrix by the rational QL

method [C. H. Reinsch, Comm. ACM 16 (1973) 689].

TRANLF

Converts Cartesian to mass-weighted coordinates or mass-weighted to Cartesian

coordinates store in lower triangular form.

TRANS

Converts Cartesian to mass-scaled coordinates or mass-scaled to Cartesian

coordinates. Also converts derivatives of the potential energy function between

these coordinate systems.

TRANS2

Converts Cartesian to mass-scaled coordinates (IOP = 1) or mass-scaled to

Cartesian coordinates (IOP = 2) used in IVTST calculations.

TRANG

Transforms gradient in Cartesians to curvilinear internal coordinates.

TRANFC

Transforms Hessian in Cartesians to curvilinear internal coordinates.

TRANSF

Converts Cartesian to mass-weighted coordinates (IOP = 1) or mass-weighted to

Cartesian coordinates (IOP = 2).

TRBAK3

Forms the eigenvectors of a real symmetric matrix by back transformation of the

eigenvectors of the similar symmetric tridiagonal matrix.

TRED3

Reduces a real symmetric matrix to a symmetric tridiagonal matrix.

TREPT

Computes a parabolic fit, F = ax2+ bx + c, to three points.

TRLFRP

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Stores the force constant matrix in lower triangle form.

TSC

Locates points where E = VaAG

and calculates the theta integral.

TSOUT

Computes and writes the final set of conventional transition state theory rate

constants. Also obtains activation energies and equilibrium constants.

TSPSI

TSPACK subroutine that computes a set of parameter values which define a

Hermite interpolatory tension spline.

TSRATE

Calculates the free energy of activation at the saddle point, individual reactant and

product partition functions, and conventional transition state theory rate constants

in the harmonic approximation. This routine is only used when the NOCVT

keyword is used in the RATE section. Some further discussion is provided in

Section 6.L of this manual.

TURNPT

Computes the concave-side turning point for the zero-point level in the

calculation of the curvature component.

UPCSE

Converts a line of characters to uppercase.

UPCAS

Converts lower case characters to upper case in the given string.

UPDHR

Updates the arrays FMIHR and FMIHTS in the VTST-IOC calculations.

UPDMI

Updates the arrays FMOM and FMITS in the VTST-IOC calculations.

VALVAG

Calculates the value of VaG for a given projected direction, given V, X, DX, and

F.

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VECCON

Normalizes the normal mode vectors and converts them to mass-scaled

Cartesians.

VECMAG

Obtains the magnitudes of a set of vectors.

VICLCG

Calculates the classical energy corrections in the non-adiabatic region for the LCT

method in the VTST-IOC calculations.

VIVT

Computes the Eckart potential and its derivatives.

VPART

Computes the vibrational partition function.

VPARTI

Computes the vibrational partition function using the harmonic approximation.

VRCNEJ

Calculate number of available states for transitional modes using variable reaction

coorindate algorithm at canonical, microcanonical, and E,J -resolved

microcanonical levels.

VRCTST

Main subroutine to calculate reaction rate for loose transition state using variable

reaction coordinate and single-faceted or multifaceted dividing surface.

VSPLIN

Generates spline fits to the vibrationally adiabatic potential curve and the

effective reduced mass.

VSPLI2

Generates spline fits to the vibrationally adiabatic potential curve and the

effective reduced mass for IVTST calculations.

VTMUSN

Calculates the microcanonical variational sum of states in the calculation of the

microcanonical variational rate constant.

WTITLE

Writes the title of the run.

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WKBENE

Calculates the energy eigenstates with the WKB approximation.

WKBPOT

Computes the energy levels of a quadratic-quartic function using a semiclassical

method with parabolic connection formulae.

WKBVIB

Driver for the calculation of WKB vibrational energies based on the true

(unfitted) potential for a given mode.

WRTHOK

Writes stationary point information to file fu61 and, if necessary, to file fu62.

WRTWEL

Writes the information about the wells to file fu6.

WVAR6

Writes the keyword values for a restart calculation.

XDOTP

Calculates the dot product of two vectors.

XERBLA

Error handler for the BLAS routines.

XPROD

Forms the cross product of vectors x and y, placing the result in vector z. All

vectors are of dimension three.

YDER24

Computes the second derivatives of the potential by fitting the analytic first

derivatives to a fourth-order polynomial around the desired location and then

taking the derivative of this polynomial. This is the hooks version of DERV24.

YDERV2

Calculates the Hessian matrix by using a quadratic fit to the potential energy

surface. Only the potential is used, not its first derivatives. This is the hooks

version of DERIV2.

YNEWT

Does a Newton-Raphson search for a stationary point. This is the hooks version

of NEWT.

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YSECEN

Calculates second derivatives by the method of central differences. This is the

hooks version of SECCEN.

YSECEP

Calculates second derivatives by the method of central differences; only computes

part of the Hessian matrix. This is the hooks version of SECCEP.

YTRANS

Converts Cartesian coordinates to mass-scaled coordinates or converts mass-

scaled coordinates to Cartesian coordinates. Also converts derivatives of the

potential energy function between these coordinate systems. This is the hooks

version of TRANS.

ZEROPT

Computes the zero-point energy.

ZERP

Function that computes the zero-point energy.

ZIGAMA

Calculates the incomplete Gamma function of order 3/2.

ZOC3P

Prepares the correction information at 3 points for the VTST-IOC calculations.

ZOCAST

Checks the accuracy of the interpolation in the VTST-IOC calculations.

ZOCFRE

Calculates the corrections for the frequencies for VTST-IOC calculations.

ZOCPAR

Calculates the parameters for the VTST-IOC calculations.

ZOCPRN

Prints some of the information involved in VTST-IOC calculations.

ZOCUPD

Updates the arrays WER, FMOM, CDSCMU, VCLAS, WETS, and VADIB and

the variables EPRD and WSTAR with zero-order corrections for VTST-IOC

calculations.

ZOCVCL

Calculates the correction for the energy VMEP in VTST-IOC calculations.

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ZRIDDR

Solves a nonlinear equation for calculating the range parameter of an Eckart

potential.

ZROUT

Explicitly initializes the work space for matrix with zeros to overcome the

FORTRAN save effect.

ZRPTE

Evaluates the zero-point energies.

ZSPMEP

Sets up information for ISPE. This subroutine is used with unit fu51.

17.A.2 User-supplied subprograms and module files

MODULE files:

aamod.f90

This FORTRAN 90 file contains all the modules used for passing

information between the various subprograms. It also contains all the

permanent constants for the Polyrate code. These parameters should not

be changed.

alloc.f90

This FORTRAN 90 file dynamically allocates memory for arrays according

to the user input file.

User-supplied subprograms:

SETUP

Subprogram supplied by the user that computes any necessary constants

for the potential (see Section 8 and examples in the test suite).

SURF

Subprogram supplied by the user that computes the potential and gradient

for a set of Cartesian coordinates (see Section 8 and examples in the test

suite).

17.A.3 FORTRAN files

acespoly.F

This file contains dummy subroutines used with ACESRATE.

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energetics.F

This file contains subprograms for the calculations of properties of the PES.

These include subprograms that handle optimizations and numerical second

derivatives.

ef.F

This file contains the Eigenvector-Following algorithm for optimizing

geometries of the stationary points.

fromblas.F

This file contains all the subroutines from the BLAS math library.

givtst.F

This file contains subprograms for the global version of IVTST calculations.

headr.F

This file contains subprograms that print out the program header.

hooks.F

This file contains subprograms for interfacing electronic structure calculations

with POLYRATE.

intbsv1.F

This file contains subprograms for the transformations of the Cartesian

Hessians into a curvilinear coordinate system at non-stationary points along

the MEP and for the curvilinear coordinate vibrational analysis for linear and

nonlinear triatomics.

intbsv2.F

This file contains subprograms for the transformations of the Cartesian

Hessians into a curvilinear coordinate system at non-stationary points along

the MEP and for the curvilinear coordinate vibrational analysis for nonlinear

polyatomics. The coordinate transformation of the Hessian is based on the

transformation ANHTRAX program written by Matt Challacombe and Jerzy

Cioslowski.

intbsv3.F

This file contains subprograms for the transformations of Cartesian Hessians

into curvilinear coordinate system at reactants and products and for the

curvilinear coordinate vibrational analysis for nonlinear polyatomic.

interface.F

This file contains subprograms for parsing Polyrate keyword input.

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ivtstm.F

This file contains subprograms for performing IVTST-M interpolation.

main.F

This file contains the driver for polyatomic VTST calculations.

main_vrcmpi.F

This file contains the driver for polyatomic VRC-TST calculations. It is a

substitution of main.F file.

mopoly.F

This file contains dummy subroutines used with MORATE.

polyag.F

This file contains subprograms with names beginning with letters A to G.

polyhl.F

This file contains subprograms with names beginning with letters H to L.

polymq.F

This file contains subprograms with names beginning with letters M to Q.

polyrr.F

This file contains subprograms with names beginning with the letter R.

polysz.F

This file contains subprograms with names beginning with letters S to Z.

poly31.F

This file contains subprograms that are used when POTENTIAL = unit31.

poly40.F This file contains subprograms that are used when POTENTIAL = unit40.

rtpjac.F

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This file contains subprograms that are used to plot the MEP and large

curvature representative tunneling termini in mass-scaled Jacobian

coordinates.

vrctst_mpi.F

This file contains subprograms that are used to calculate reaction rate

for loose transition states using variable reaction coordinates and

single-faceted or multifaceted dividing surfaces. These subprograms

are parallelized using MPI.

17.B. Utility program detmi.f

In this version of POLYRATE, one of the VTST-IOC options [DETMI keyword] allows the

user to correct the calculated determinants of moment of inertia tensors with accurate

data. However, the values of determinants of moment of inertia tensors are not always

available in the literature or in the electronic structure calculation output of standard

codes. So, in this version of the Polyrate distribution we provide a small utility program,

detmi.f, in the util subdirectory of the POLYRATE17 directory. This program reads a

molecular geometry in Cartesians (in bohrs or in Angstroms) and the atomic weights (in

a.m.u.) of the constituent atoms of the molecule, and calculates the determinant of the

moment of inertia tensor of the molecule in all the units supported by the Polyrate unit

fu50 input options [UNITMI keyword]. (See subsection 12.F) The input formats are very

simple, and a detailed explanation can be found in the file detmi.doc in the same

subdirectory. A job control file detmi.jc and three sample input files, ch4.mi, ch4oh.mi,

and oh.mi are also provided.

One can use the compiling and linking commands listed in the Section 15 of this manual

to make an executable file detmi.exe for any machine. This program is easy to use;

however, one has to remember to do the following:

1. Make a data file. The program will read the data from a file called detmi.dat.

If your data file has a different name, copy, move, or link your file to this

name.

2. When finished, the program will generate an output file called detmi.out. It is

recommended that you move (or copy) this file to another file name before

doing any other calculations. Otherwise the new output will overwrite the old

detmi.out file, and the old information in that file will be lost.

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3. There is a simple script detmi.jc in the same sub directory. It can do the above

file copying steps for you if you want. It takes the input file name as the only

argument.

For example, if your data file is called ch4.mi, type

detmi.jc ch4.mi <Return>

to do the calculation. The output will be written to the file detmi.out and copied to

the file ch4.out.

How to make an input data file:

1. In the first line you have to input three numbers in free format.

The first number is the number of atoms in the molecule.

The second number specifies if the geometry of the molecule is linear or

nonlinear. Set the number to 1 if it is linear. Set the number to 0 if the

geometry is not linear.

The third number specifies the input units for the Cartesians. Set it to 1 if the

units you use are Angstroms. Set the number to 0 if you use bohrs.

For example, if the target molecule is methane and your geometry data in

Cartesians are in Angstroms, the first line should look like the following:

5 0 1

2. The second and the third lines are the calculation titles. You can write whatever you

want here (less than 80 characters in one line).

For example:

Methane: CH4

QCISD/adj-cc-pVTZ geometry

3. The next n lines, where n is the first number you entered in the first line,

contains the atomic masses and Cartesian coordinate information. There

should be 4 numbers on each line. The first number is the atomic mass in

a.m.u. of the atom; the second, third, and fourth numbers are the x, y, and z

coordinates of the atom.

For example:

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1.007825 0.0000 0.0000 0.0000

12.00000 1.0848 0.0000 0.0000

1.007825 1.4464 1.0228 0.0000

1.007825 1.4464 -0.5114 0.8857

1.007825 1.4464 -0.5114 -0.8857

17.C. Utility program hrotor.f

When some of the vibrational modes of the reactants, products, or GTS are treated as

hindered rotations, Polyrate allows the user to input more accurate values of the moments

of inertia of these modes in a VTST-IOC calculation [IC and HRMI keywords]. However,

usually the user can only get the geometry of a molecule and the vibrational eigenvectors

of these modes from an electronic structure calculation output.

The utility program hrotor.f is designed to take the atomic masses and geometry of the

molecule and the vibrational eigenvector of a hindered-rotor mode of the molecule and

then to calculate the moment of inertia using rectilinear model. It can also calculate the

harmonic, free rotor, and hindered rotor partition functions at different temperatures.

Detailed explanations can be found in the file hrotor.doc in the Polyrate17/util directory

and in Refs. 24, 29, and 30 in Sect. 21. A sample input file, cwmc.rmi, is also provided

in the Polyrate17/util directory.

You can use the compiling and linking commands listed in the Section 15 of this Polyrate

manual to make an executable file hrotor.exe for your machine. The program is designed

to read data from Unix standard input and write data to Unix standard output. To use the

program, type

hrotor.exe < input_file_name > output_file_name <Return>

For example:

hrotor.exe < cwmc.rmi > cwmc.rmi.out <Return>

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To make a data file follow the steps below:

(Note: All the input data are in free format.)

1. In the first line you have to input 4 numbers.

The first number is the number of atoms in the molecule.

The second number specifies the units of the Cartesian coordinates you are

going to input. Set it to 0 if you use bohrs, to 1 if you use Angstroms.

The third number specifies the coordinate system of the vibrational

eigenvector you are going to input. Set it to 0 if you use a mass-scaled

coordinate system; set it to 1 if you use a non-mass-scaled Cartesian

coordinate system.

The fourth number specifies the number of temperatures at which you want to

calculate the partition function.

For example, if the target molecule is the saddle point of the reaction in the

Polyrate cwmctrl test run, your geometry data in Cartesians are in bohrs, the

eigenvector is in mass-scaled coordinates, and you want to calculate the

partition function at two temperatures, the first line should look like the

following:

9 0 0 2

2. The second and the third lines are the calculation titles. You can write

whatever you want here (less than 80 characters in one line).

For example:

Saddle point of the reaction in cwmc test run

The moment of inertia

3. If you set the third number in the first line to 1, skip this step. The next line is

the scaling mass in a.m.u. of the mass-scaled coordinate system which the

input eigenvector is based on.

For example:

1.0000

4. The next n lines, where n is the first number you entered in the first line,

contain the atomic masses of the constituent atoms in a.m.u.

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For example:

12.00000

34.96885

1.007825

1.007825

1.007825

34.96885

1.007825

1.007825

15.99491

5. The next n lines, where n is the first number you entered in the first line,

contain the geometry data of the molecule in (unscaled) Cartesian coordinates.

There should be 3 numbers on each line, namely the x, y, and z coordinates of

the atom.

For example:

2.0187 -2.3695 0.1399

1.7442 -2.3695 4.4447

4.0466 -2.3695 0.1399

1.0334 -4.1335 0.1399

1.0334 -0.6054 0.1399

1.7442 -2.3695 -4.1650

-2.3564 -2.3695 1.5703

-2.3564 -2.3695 -1.2906

-3.4890 -2.3695 0.1399

6. The next n lines, where n is the first number you entered in the first line,

contain the vibrational eigenvector of this hindered-rotor mode. There should

be 3 numbers on each line, the x, y, and z components of the eigenvector for

the atom corresponding to this line.

For example:

0.000 0.567 0.000

0.000 -0.260 0.000

0.000 0.533 0.000

0.308 -0.008 0.000

-0.308 -0.008 0.000

0.000 -0.260 0.000

0.000 -0.116 0.000

0.000 -0.116 0.000

0.000 0.207 0.000

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7. The next line contains the symmetry and subgroup information. The first

number is the symmetry factor of this hindered rotation. The second number is

the number of atoms in one of the subgroups. The next m numbers, where m is

the second number in this line, are the atom indices of those atoms in that

subgroup.

For example:

3 4 1 3 4 5

8. If you decide to calculate the partition function (i.e., if the fourth number in

the first line is greater than 0) you need to input the harmonic frequency in

cm-1 in a new line and the temperatures in Kelvin in the last line.

For example:

163.4794

600.00 1000.00

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17.D. Utility programs findl.f and findb.f

In VTST-IOC calculations one has to input some range parameters for the correction

functions, in particular, the range parameter L for the Eckart function and the parameter B

for the cut-off Gaussian function on the reactant and/or product side. These parameters

are usually obtained by fitting a lower-level potential energy curve to the corresponding

functions. The utility programs findl.f and findb.f, which are located in the

Polyrate17/util subdirectory, are designed to do the fitting and return the optimized

values of L and B. The user can use the compiling and linking commands in Section 15 of

this Polyrate manual to make executable files (e.g., findl.exe and findb.exe). To use

these programs, just type the name of the executable file, and you will be prompted to

input the energies of 3 stationary points for findl.exe, or the energies of 2 stationary

points and the s value for one of the stationary points for findb.exe. Then, for both

programs, you will be prompted to input the energy and s value for another point along

the lower-level reaction path. This point is usually chosen to be the point that has an

energy halfway between the saddle point and the stationary point on the endothermic side

of the MEP for findl.exe or the reactant/product side stationary point for findb.exe. The

programs will then print the optimized value of L or B for the Eckart or cut-off Gaussian

function, respectively. The user can then use these values for the unit fu50 input

[RANGEIC keyword].

17.E. Utility program rotate30.f, rotate31.f, and rotate40.f

ROTATEx (x = 30, 31, or 40) is a FORTRAN program that uses as an input file a Polyrate

poly.fu30, poly.fu31, or poly.fu40 input file and orients the geometries on that file in a

consistent way along the reaction path. This program is based on the Chen orientation

algorithm Ref. 60 of Section 22.

The poly.fu30, poly.fu31, and poly.fu40 input files for Polyrate are usually constructed

from electronic structure calculations carried out by one of the several available

packages. These packages usually re-orient the input geometry in a way that allows the

program to take advantage of the symmetry of the system, or just to put the molecule in

the orientation preferred by the program. As a consequence, the input geometry is

oriented in a different way than the output geometry, gradients, and/or Hessians. This

results errors in: 1) reaction path following algorithms and 2) computation of reaction

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path curvature. If we do not calculate the reaction path or the curvature of the reaction

path, the properties that Polyrate uses for the dynamical calculations are rotationally

invariant, and the results will not be affected by any rotation of any geometry. However,

if we want to calculate the reaction path curvature, we need to calculate the derivatives of

the Cartesian components of the gradient with respect to the reaction coordinate s. For

doing this, we require that all the points along the reaction path be oriented in the same

way. Otherwise, the numerical differentiation will lead to erroneous results.

The ROTATEx program uses a geometry that is input by the user (this is assumed to be the

saddle point geometry), and it reorients the first point along each side of the reaction path

according to this point. The following points along the reaction path are reoriented using

as reference geometry the previous point. This reorientation is done by means of the

Chen algorithm, as described in the original paper. However, this algorithm only works

for small rotations, so before applying Chen's method the program performs a series of

trial rotations in order to obtain the closest orientation to the reference geometry, and next

it applies Chen's method on the most similar orientation.

Chen's method is based on the minimization of the distance in mass-scaled Cartesian

coordinates of the two geometries. In some cases, this minimization does not converge.

When that happens, there is no way to solve the reorientation problem with this program.

The program can also recalculate the values of the reaction coordinate, s, as a straight line

between each pair of two consecutive points. This recalculation can be useful, e.g., for

calculating kinetic isotope effects.

There are three versions of the program ROTATEx: ROTATE30, ROTATE31, and ROTATE40,

and they are used for reorienting the geometries in poly.fu30, poly.fu31, and poly.fu40

input files, respectively. In order to perform this rotation it is necessary to

give the geometry of each point. This is sometimes not given on the poly.fu30 and

poly.fu40 input files. Thus, when we supply additional information on the gradients of

one or two points on each side of the Hessian points in poly.fu30 or poly.fu40, the

geometry of these one or two additional points per Hessian point is not given. This is the

reason why only poly.fu30 files with LOPT(6) = 2 will work with ROTATE30, and only

poly.fu40 input files with GRADER = NOEXTRA will work with ROTATE 40.

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An additional limitation of the program is that it only works with poly.fu30 and poly.fu40

input files that do not include any anharmonic information.

Along with the source code, a test run is included for each program, as well as a sample

script for compiling and running the code.

The program requires two input files: (1) one of the Polyrate input files poly.fu30,

poly.fu31, or poly.fu40, and (2) a input file for the ROTATE program. The latter input file

is described next.

The first line of the input file consists of seven integers that indicate the number of atoms

in each system. The first integer is NATOM, the number of atoms in the saddle point

structure (which is assumed to be the same as the number of atoms for the points along

the reaction path) followed by six integers indicating the number of atoms in the first

reactant species, the second reactant, the first product, the second product, the reactants

well, and the products well, respectively. If one or more of these species don't exist, a

zero has to be input in its place.

The second line is a list of NATOM + 1 real numbers. The first one indicates the mass used

for scaling the Cartesian coordinates (which has to be the same as SCALEMASS in the

PATH section of the Polyrate poly.fu5 input file. The following NATOM real numbers are

the masses of each of the atoms present in the points along the reaction path, in the same

order as in in these points. All the masses have to be input in amu.

The third line is an integer that indicates if the values of s read from the poly.fu30,

poly.fu31, or poly.fu40 input files have to be kept unchanged or if the user wants to put in

their places the values computed by the program. If this integer is set to one, the values of

s that are read are discarded, and the calculated values are printed in the output file. Any

other value leads the program to preserve the s values that are input in the poly.fu30,

poly.fu31, or poly.fu40 input file.

The last information to be input in the ROTATE input file is the geometry in Cartesian

coordinates of the saddle point in atomic units. The three Cartesian coordinates for each

atom have to be preceded by an integer, which acts as a label. The ordering of the atoms

has to be the same as in the points along the reaction path, and the labels have to start

with the integer 1 for the first atom and finish with the integer NATOM for the last atom.

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The output of the program, poly.fu60, is a file with the format same as poly.fu30,

poly.fu31, or poly.fu40, which can be used in a Polyrate calculation directly without

further modification.

17.F. Utility program SS-QRRK

The utility program directory SS-QRRK contains one .exe file, one source code file

(.f90), one directory for test runs, and one directory for outputs of test runs. SS-QRRK

code is a FORTRAN90 code for carrying out system-specific quantum RRK calculations.

Please refer to a separate manual for the use of SS-QRRK code.

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18. UNIX C SHELL SCRIPTS AND PERL SCRIPTS

Polyrate includes many useful scripts for users. The following subsections discuss the

functions of these scripts and explain how to use them.

18.A. Installation script

This script, configure, resides in the Polyrate17 directory. It is used to install the Polyrate

program on your computer. Note that this installation is only for generating the Makefile,

and no executable is generated in this process. Usually, the first thing you do after

uncompressing and untarring the distribution tar file is to run this script. (See Subsection

15.A.) Actually, this script does four things:

1. Makes a hidden file .poly_path in your home directory.

The hidden file contains the path to the Polyrate17 directory in the file system you

are using. This lets other scripts in Polyrate easily locate the necessary files. If you

lose the hidden file for some reason, or if the file system changes after you install

POLYRATE, you need to run this script again to generate a new .poly_path file.

2. Asks the user to choose which kind of executable the user wants the Makefile to

generate: RP-VTST or VRC-VTST. (If you want both, you must run the script twice.)

3. Detects compilers, operating system, and processor type

The script will automatically search for the FORTRAN and C compilers that are

correct for the configuration being used.

4. Copies machine-dependent files and puts them into the proper directories with the

default file names.

It copies the appropriate date-and-time routine from the Polyrate17/util directory to

the Polyrate17/src directory and names it dattim.f.

If VRC-VTST installation is selected by the user, the script will install the SPRNG

2.0 library. If RP-VTST installation is chosen, the script will skip the SPRNG

installation step.

5. Creates the Makefile

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The Makefile is used to compile and link all of the code needed for a job. If any

changes are made to the files used to create the executable, the Makefile will

automatically update the executable.

See section 15.A.1 for a description of the directory structure following a successful

installation.

18.B. Potential energy surface compiling scripts

This script is distributed in the current version, but it is no longer needed when using

Makefile.

There are two potential energy surface subroutine compiling scripts in the

Polyrate17/script directory. The script comp_pot.jc is used to compile all the potential

energy surface subroutines for the test runs. (See Subsection 15.A.2.)

The script potcomp.jc is designed to compile a single file of potential energy surface

subroutines. It is general, and you can use it to compile your own potential subroutines.

This script takes two arguments; the first one is the potential file name without extension,

and the second one is the number of atoms involved in the potential. For example,

suppose you have a set of FORTRAN potential energy subroutines which defines the

potential energy surface of a system that consists of one oxygen atom and 3 hydrogen

atoms, and the set of subroutines has the file name myoh3.f. Put this file in the

Polyrate17/poten directory. You then change to the Polyrate17/script directory and type

potcomp.jc myoh3 4 <Return>; the script will compile the file myoh3.f for you and put

the object module myoh3.o in the Polyrate17/obj directory. You can, if you wish, copy

the script into the Polyrate17/poten directory so you can use it more conveniently.

Remember that you must put your potential source code in the Polyrate17/poten

directory. It should be noted that since the nh3 potential energy surface subroutine

provided in the distribution package has already been written the way that is required by

POLYRATE, when compiling this potential energy subroutine with the script potcomp.jc,

you should use a number that is not 3 or 4 as the second argument. This is because the

nh3.f subprogram already contains the necessary SETUP, SURF, COORD, and CHAIN

subroutines.

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18.C. Source code compiling script

This script is distributed in current, but it is no longer needed when using Makefile.

The script comp_src.jc in the script/ directory is used for compiling the Polyrate source

code. It takes one argument, the parameter INCLUDE file number. You probably used this

script when you did the testing. (See Subsection 15.A.2.) Usually, after you compile the

source code with a certain parameter INCLUDE file and keep the library file that the script

generated, you don't need to recompile the source code unless you need to use a different

parameter INCLUDE file. For example, suppose you write your own INCLUDE file named

param5.inc, and you want to compile the source code with this INCLUDE file. Put the

param5.inc file in the src/ directory, change to the script/ directory, and type comp_src.jc

5 & <Return>. The script will compile the source code with the parameter INCLUDE file

param5.inc and generate a library file named libpoly5.a in the obj/ directory. You can

then use the linking script described in the next subsection to link this library file with

your potential object module to make an executable file. Remember that you must put

the parameter INCLUDE file in the src/ directory and always name a new parameter file

param#.inc where # can be any integer greater than 4.

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18.D. Linking script

This script is distributed in the current version, but it is no longer needed when using

Makefile.

The script link_exe.jc in the Polyrate17/script directory is used for linking the potential

object file with the source code library file to make an executable file. It takes 2

arguments. The first one is the library file number, which is just the parameter INCLUDE

file number you used when making the source code library file. (See the Subsection

above.) The second argument is the potential file name (without the extension) you want

to use. For example, if you want to use the source code library compiled with the

parameter file param5.inc and the potential object module myoh3.o to make an

executable file, change your working directory to the script/ directory and type

link_exe.jc 5 myoh3 <Return>. The script will link the source code library and potential

object files together and generate the executable file poly_myoh3.exe and a short

summary file poly_myoh3.doc about this new executable file in the exe/ directory.

18.E. Test run scripts

The test run scripts have been discussed in Subsection 15.A.2. These scripts are designed

such that you don't need to know much about Polyrate in order to run the test runs. Some

of the test runs might take a long time to run (see Sect. 21) so you should consider

running them in background or submitting them as batch jobs. Some test runs generate

very big output files that you may want to delete together with the test run executable

files when you need to free up some disk space.

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19. FILE USAGE

The Polyrate program uses several files for input data, for storing restart information

(optional), and for output. The program explicitly opens and closes all files required for a

given run, and the files are assumed to have the file names poly.fu#, where # is an

integer. The file poly.fu# connects to a FORTRAN I/O unit fu# which is defined in the

file aamod.f90 (see Subsection 5.A). This means that at the beginning of any run, all the

Polyrate input data files which have logical file names differing from poly.fu# must be

linked or copied to the corresponding poly.fu# file. If the user wishes to assign different

logical names to the output files, which are also poly.fu# files, these reassignments must

be carried out after the calculation has completed. Any data file(s) needed by the

potential energy surface subroutine is (are) not opened by the Polyrate program and

therefore, do not automatically follow the poly.fu# format.

One would ordinarily expect FORTRAN unit 5 to be assigned to fu5, FORTRAN unit 6

to fu6, and so forth. The fu# system, however, allows one to avoid conflicts when

hooking Polyrate up to other programs, e.g., MOPAC or analytic potentials.

Unit Usage

fu1 Reaction-path information for restarting the program

fu2 Additional reaction-path information to be merged with that

from unit fu1

fu3 Output for merged reaction path information

fu4 Reserved for potential energy surface data

(Note: A potential subroutine may read data from more than

one file, if desired. In the test suite we always use unit 4 if data

is read from only one file, and we use units 4 and 7 for the

cases where data is read from two files)

fu5 General input data. This data has several sections—see section

12.A of this manual for the details.

fu6 Output (This is the full output file. Selected subsets of this

output are also written to files poly.fu14 and poly.fu15)

fu7 Usually reserved for additional potential energy surface data

(See Subsections 8.C and 16.B for further discussion)

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fu14 Output table of dynamical bottleneck properties

fu15 Output table of selected forward rate constants

fu16 Reserved for output from electronic structure packages

fu22 Detailed output for the LCT calculations [LCTOPT: PRFREQ,

PRPROB]

fu24 Output file of MEP and large curvature representative tunneling

termini in mass-scaled Jacobian coordinates.

fu25 Output file of the potential energy information along the MEP

fu26 Output file of the generalized transition state frequency

information along the MEP

fu27 Generalized transition state geometry information along the

MEP in the XYZ input format of the XMOL program

fu28 Bond angles, bond distances, and dihedral angles along the

MEP

fu29 Electronic structure input file for IVTST-0 and IVTST-1

calculations

fu30 Formatted electronic structure input file used if POTENTIAL =

unit 30 in the ENERGETICS Section of file fu5

fu31 Keyword-based electronic structure input file used if POTENTIAL = unit31 in the ENERGETICS section of file fu5.

fu40 Keyword-based electronic structure input file used if

POTENTIAL = unit40 in the ENERGETICS section of file fu5

fu41–fu47 Output tables of LCT calculations [LCTDETAIL]

fu48,fu49 Output files for LCT restart calculations

fu50 Input file for higher-level data for VTST-IOC calculations [DL

keyword set to ioc or ICOPT]

fu51 Input file for higher-level data for VTST-ISPE calculations [DL keyword set to ispe]

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fu60 Reserved for the direct dynamics intermediate file

fu61 Reserved for information about stationary points that can be

used to restart a calculation by the second restart method of

Section 7. C.

fu62 Reserved for a subset of information that are presented in fu61

if the argument of the WRITE62 keyword is not set to none

fu65 Generalized transition state geometry information along the

MEP in the XYZ input format of the MDMOVIE program

fu70 Reserved for input data needed by PREP

fu71 Reserved for input data needed by PREPJ when JTYPE = 1

(REACT1)

fu72 Reserved for input data needed by PREPJ when JTYPE = 2

(REACT2)

fu73 Reserved for input data needed by PREPJ when JTYPE = 3

(PROD1)

fu74 Reserved for input data needed by PREPJ when JTYPE = 4

(PROD2)

fu75 Reserved for input data needed by PREPJ when JTYPE = 5

(START)

fu76 Reserved for input data needed by PREPJ when JTYPE = 6

(PATH)

fu77 Reserved for input data needed by PREPJ when JTYPE = 7

(WELLR)

fu78 Reserved for input data needed by PREPJ when JTYPE = 8

(WELLP)

fu80-fu89 Reserved for electronic structure codes and interfaces

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20. CITATIONS INDICATED BY BRACKETS IN THE TEXT

[1] R. E. Weston, Jr. and H. A. Schwarz, Chemical Kinetics (Prentice-Hall,

Englewood Cliffs, 1972), p. 101.

[2] I. Shavitt, Theoretical Chemistry Laboratory Report No. WIS-AEC-23 (University

of Wisconsin, Madison, 1959); R. E. Weston, Jr., J. Chem. Phys. 31 (1959) 892; I.

Shavitt, J. Chem. Phys. 49 (1968) 4048.

[3] R. A. Marcus, J. Chem. Phys. 45 (1966) 4493; 49 (1968) 2610, 2617.

[4] D. G. Truhlar and A. Kuppermann, J. Chem. Phys. 52 (1970) 3842; J. Amer.

Chem. Soc. 93 (1971) 1840.

[5] K. Fukui, in The World of Quantum Chemistry, R. Daudel and B. Pullman, Eds.

(Reidel, Dordrecht, 1974), p. 113.

[6] B. C. Garrett and D. G. Truhlar, J. Chem. Phys. 70 (1979) 1593.

[7] W. H. Miller, N. C. Handy, and J. E. Adams, J. Chem. Phys. 72 (1980) 99.

[8] G. Herzberg, Infrared and Raman Spectra of Polyatomic Molecules (D. van

Nostrand, Princeton, NJ, 1945), pp. 505-10.

[9] D. A. McQuarrie, Statistical Mechanics (Harper & Row, New York, 1976), pp.

133-6.

[10] B. C. Garrett, D. G. Truhlar, R. S. Grev, and A. W. Magnuson, J. Phys. Chem. 84

(1980) 1730, 87 (1983) 4554E.

[11] R. T. Skodje, D. G. Truhlar, and B. C. Garrett, J. Phys. Chem. 85 (1981) 3019.

[12] B. C. Garrett, N. Abusalbi, D. Kouri, and D. G. Truhlar, J. Chem. Phys. 83 (1985)

2252.

[13] D. G. Truhlar and B. C. Garrett, Accounts Chem. Res. 13 (1980) 440.

[14] W. H. Press, B. P. Flannery, S. A. Teukolsky, and W. T. Vetterling, Numerical

Recipes (Cambridge University Press, Cambridge, 1986), p. 412.

[15] ibid., p. 418-422.

[16] ibid., p. 283.

[17] M. Page and J. W. McIver, Jr., J. Chem. Phys. 88 (1988) 922.

[18] B. C. Garrett and D. G. Truhlar, J. Phys. Chem. 83 (1979) 200, 1052, 83 (1979)

3058E, 87 (1983) 4553E.

[19] K. Ishida, K. Morokuma, and A. Komornicki, J. Chem. Phys. 66 (1977) 2153.

[20] M. W. Schmidt, M. S. Gordon, and M. Dupuis, J. Amer. Chem. Soc. 107 (1985)

2585.

[21] L. D. Landau and E. M. Lifshitz, Quantum Mechanics, 2nd ed. (Pergamon,

Oxford, 1965), p. 163.

[22] J. N. L. Connor, Chem. Phys. Lett. 4 (1969) 419.

[23] S. C. Tucker and D. G. Truhlar, J. Amer. Chem. Soc. 112 (1990) 3338.

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[24] X. G. Zhao, D.-h. Lu, Y.-P. Liu, G. C. Lynch, and D. G. Truhlar, J. Chem. Phys.

97 (1992) 6369.

[25] T. N. Truong and D. G. Truhlar, J. Chem. Phys. 93 (1990) 2125.

[26] V. K. Babamov, V. Lopez, and R. A. Marcus, J. Chem. Phys. 78 (1983) 5621.

[27] X. G. Zhao, A. Gonzalez-Lafont, D. G. Truhlar, and R. Steckler, J. Chem. Phys. 94

(1991) 5544.

[28] A. J. C. Varandas, F. B. Brown, C. A. Mead, D. G. Truhlar, and N. C. Blais,

J. Chem. Phys. 85 (1987) 6258.

[29] C. F. Melius and R. J. Blint, Chem. Phys. Lett. 64 (1979) 183.

[30] S. P. Walch and T. H. Dunning, J. Chem. Phys. 72 (1980) 72.

[31] G. C. Schatz and H. Elgersma, Chem. Phys. Lett. 73 (1980) 21.

[32] T. N. Truong and D. G. Truhlar, J. Phys. Chem. 94 (1990) 8262.

[33] C. Y. Lee and A. E. DePristo, J. Chem. Phys. 85 (1986) 4161.

[34] S. C. Tucker and D. G. Truhlar, J. Phys. Chem. 93 (1989) 8138.

[35] R. Q. Topper, Q. Zhang, Y.-P. Liu, and D. G. Truhlar, J. Chem. Phys. 98 (1993)

4991.

[36] E. B. Wilson, Jr., J. C. Decius, and P. C. Cross, Molecular Vibrations,

(MacGraw-Hill, New York, 1955).

[37] G. Fogarasi and P. Pulay, in Vibrational Spectra and Structure, Vol. 14, edited by

J. R. Durig (Elsevier, Amsterdam, 1985), p. 125.

[38] M. A. Pariseau, I. Suzuki, and J. Overend, J. Chem. Phys. 42 (1965) 2335.

[39] A. R. Hoy, I. M. Mills, and G. Strey, Mol. Phys. 24 (1972) 1265.

[40] J. Cioslowski and M. Challacombe, ANHTRAX, QCPE Program No. 609 (Quantum

Chemistry Program Exchange, Bloomington, IN, 1991).

[41] M. Challacombe and J. Cioslowski, J. Chem. Phys. 95 (1991) 1064.

[42] D. G. Truhlar and A. D. Isaacson, J. Chem. Phys. 94 (1991) 357.

[43] D. G. Truhlar, N. J. Kilpatrick, and B. C. Garrett, J. Chem. Phys. 78 (1983) 2438.

[44] B. C. Garrett and D. G. Truhlar, J. Chem. Phys. 72 (1980) 3460.

[45] D. G. Truhlar, J. Chem. Soc. Faraday Trans. 90 (1994) 1740.

[46] D. G. Truhlar and M. S. Gordon, Science 249 (1990) 491.

[47] D. G. Truhlar, B. C. Garrett, and S. J. Klippenstein, J. Phys. Chem. 100 (1996)

12771.

[48] T. N. Truong, J. Chem. Phys. 100 (1994) 8014.

[49] B. C. Garrett and D. G. Truhlar, J. Phys. Chem. 83 (1979) 1079.

[50] S. L. Mielke, D. G. Truhlar, and D. W. Schwenke, J. Phys. Chem. 99 (1995)

16210.

[51] B. C. Garrett and D. G. Truhlar, J. Chem. Phys. 66 (1982) 1853.

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[52] J. C. Corchado, J. Espinosa-Garcia, O. Roberto-Neto, Y.-Y. Chuang, and D. G.

Truhlar, J. Phys. Chem. A 102 (1998) 4899.

[53] T. C. Allison and D. G. Truhlar, in Modern Methods for Multidimensional

Dynamics Computations in Chemistry, edited by D. L. Thompson (World

Scientific, Singapore, 1998), p. 618.

[54] J. Backer, F. Jensen, H. S. Rzepa, A. Stebbings, Location of Transition States in

AMPAC and MOPAC Using Eigenvector Following (EF), QCPE Program No. 597

(Quantum Chemistry Program Exchange, Bloomington, IN, 1990).

[55] A. Banerjee, N. Adams, J. Simons, and R. Shepard, J. Phys. Chem. 89 (1985) 52.

[56] J. Baker, J. Comp. Chem. 7 (1985) 385.

[57] P. Culot, G. Dive, V. J. Nguyen, and J. M. Ghuysen, Theor. Chim. Acta 82 (1992)

189.

[58] T. Helgaker, Chem. Phys. Lett. 182 (1991) 503.

[59] K. S. Pitzer, J. Chem. Phys. 14 (1946) 239.

[60] Z. Chen, Theor. Chim. Acta 75 (1989) 481.

[61] T. Yu, J. Zheng, and D. G. Truhlar, Chem. Sci. 2 (2011) 2199.

[62] T. Yu, J. Zheng, and D. G. Truhlar, J. Phys. Chem. A 116 (2012) 297.

[63] J. Zheng and D. G. Truhlar, Faraday Discuss. 157 (2012) 59.

[64] J. Zheng, S. L Mielke, K. L Clarkson, and D. G. Truhlar, Computer Phys.

Commun. 183 (2012) 1803.

[65] J. Zheng, R. Meana-Pañeda, and D. G. Truhlar, Computer Phys. Commun.184

(2013) 2032.

[66] J. Zheng, S. L Mielke, K. L Clarkson, R. Meana-Pañeda, and D. G. Truhlar,

MSTOR, (University of Minnesota, Minneapolis, 2014).

http://comp.chem.umn.edu/mstor

[67] A. Fernández-Ramos, B. A. Ellingson, R. Meana-Pañeda, J. M. C. Marques, and

D. G. Truhlar, Theor. Chem. Acc. 118 (2007) 813.

[68] J. Zheng and D. G. Truhlar, J. Chem. Theory Comput. 9 (2013) 2875.

[69] I. M. Alecu, J. Zheng, Y. Zhao, and D. G. Truhlar, J. Chem. Theory Comput. 6

(2010) 2872.

[70] J. Zheng, T. Yu, E. Papajak, I, M. Alecu, S. L. Mielke, and D. G. Truhlar, Phys.

Chem. Chem. Phys. 13 (2011) 10885.

[71] J. Zheng and D. G. Truhlar, J. Chem. Theory Comput. 9 (2013) 1356.

[72] J. L. Bao, R. Meana-Pañeda, and D. G. Truhlar, Chem. Sci. 6 (2015), 5866.

[73] J. L. Bao, J. Zheng, and D. G. Truhlar, J. Am. Chem. Soc. 138 (2016), 2690.

[74] J. L. Bao, X. Zhang, and D. G. Truhlar, Phys. Chem. Chem. Phys. 18 (2016),

16659.

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[75] “Barrierless association of CF2 and dissociation of C2F4 by variational transition

state theory and system-specific quantum Rice–Ramsperger–Kassel theory,” J. L.

Bao, X. Zhang, and D. G. Truhlar, Proceedings of the National Academy of

Sciences, U.S.A., 113, (2016), 13606.

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21. BIBLIOGRAPHY

Note : See Sect. 20 for references indicated by brackets in the text of the manual.

The following is a list of some publications reporting calculations carried out with

Polyrate or with its very much older version, which was entitled ICVTST. This includes

all articles in which new procedures incorporated in Polyrate are described, but it does

not include all applications.

1. “Polyatomic Canonical Variational Theory for Chemical Reaction Rates. Separable-

Mode Formalism with Application to OH + H2 → H2O + H”, A. D. Isaacson and D.

G. Truhlar, J. Chem. Phys. 76, 1380 (1982).

2. “The Incorporation of Quantum Effects in Generalized Transition State Theory”, D.

G. Truhlar, A. D. Isaacson, R. T. Skodje, and B. C. Garrett, J. Phys. Chem . 86, 2252

(1982); erratum: 87, 4554 (1983).

3. “Statistical-Diabatic Model for State-Selected Reaction Rates. Theory and

Application of Vibrational-Mode Correlation Analysis to OH(nOH) + H2(nHH) →

H2O + H”, D. G. Truhlar and A. D. Isaacson, J. Chem. Phys. 77, 3516 (1982).

4. “Variational Transition State Theory Calculations for an Atom-Radical Reaction

with no Saddle Point: O + OH”, S. N. Rai and D. G. Truhlar, J. Chem. Phys. 79,

6049 (1983).

5. “Generalized Transition State Theory”, D. G. Truhlar, A. D. Isaacson, and B. C.

Garrett, in The Theory of Chemical Reaction Dynamics, edited by M. Baer (CRC

Press, Boca Raton, FL, 1985), Vol. 4, pp. 65-137.

6. “Improved Canonical and Microcanonical Variational Transition State Theory

Calculations for a Polyatomic System: OH + H2 → H2O + H”, A. D. Isaacson, M.

T. Sund, S. N. Rai, and D. G. Truhlar, J. Chem. Phys. 82, 1338 (1985).

7. “Semiclassical Reaction-Path Methods Applied to Calculate the Tunneling Splitting in NH3”, F. B. Brown, S. C. Tucker, and D. G. Truhlar, J. Chem. Phys. 83, 4451

(1985).

8. “Diffusion of Hydrogen, Deuterium, and Tritium on the (100) Plane of Copper:

Reaction-Path Formulation, Variational Transition State Theory and Tunneling

Calculations”, J. G. Lauderdale and D. G. Truhlar, Surface Science 164, 558

(1985).

9. “Embedded-Cluster Model for the Effect of Phonons on Hydrogen Surface

Diffusion on Copper”, J. G. Lauderdale and D. G. Truhlar, J. Chem. Phys. 84, 1843

(1986).

10. “Test of Variational Transition State Theory and the Least-Action Approximation

for Multidimensional Tunneling Probabilities Against Accurate Quantal Rate

Constants for a Collinear Reaction Involving Tunneling into an Excited State”, B.

C. Garrett, N. Abusalbi, D. J. Kouri, and D. G. Truhlar, J. Chem. Phys. 83, 2252

(1985).

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11. “The Representation and Use of Potential Energy Surfaces in the Wide Vicinity of a

Reaction Path for Dynamics Calculations on Polyatomic Reactions”, D. G. Truhlar,

F. B. Brown, R. Steckler, and A. D. Isaacson, in The Theory of Chemical Reaction

Dynamics, edited by D. C. Clary (D. Reidel, Dordrecht, Holland, 1986), pp. 285.

12. “Semiclassical Variational Transition State Calculations for the Reactions of H and D with Thermal and Vibrationally Excited H2”, B. C. Garrett, D. G. Truhlar, A. J.

C. Varandas, and N. C. Blais, International J. Chem. Kinetics 18, 1065 (1986).

12A. “Evaluation of Dynamical Approximations for Calculating the Effect of Vibrational

Excitation on Reaction Rates”, B. C. Garrett, D. G. Truhlar, J. M. Bowman, and AF

Wagner, J. Phys. Chem. 90, 4305 (1986).

13. “Reaction-Path Analysis of the Tunneling Splitting in Fluxional Molecules:

Application to the Degenerate Rearrangement of Hydrogen Fluoride Dimer”, G. C.

Hancock, P. A. Rejto, R. Steckler, F. B. Brown, D. W. Schwenke, and D. G.

Truhlar, J. Chem. Phys. 85, 4997 (1986).

14. “POLYRATE: A General Computer Program for Variational Transition State Theory

and Semiclassical Tunneling Calculations of Chemical Reaction Rates”, A. D.

Isaacson, D. G. Truhlar, S. N. Rai, R. Steckler, G. C. Hancock, B. C. Garrett, and

M. J. Redmon, Comp. Phys. Comm. 47, 91 (1987).

15. “Surface Diffusion of H on Copper: The Effect of Phonon-Adsorbate Coupling on

the Diffusion Rate”, T. N. Truong and D. G. Truhlar, J. Phys. Chem. 91, 6229

(1987).

16. “A Comparative Study of Potential Energy Surfaces for CH3 + H2→ CH4 + H”, R.

Steckler, K. Dykema, F. B. Brown, D. G. Truhlar, and T. Valencich, J. Chem. Phys.

87, 7024 (1987).

17. “A New Potential Energy Surface for the CH3 + H2 → CH4 + H Reaction:

Calibration, Rate Constants, and Kinetic Isotope Effects by Variational Transition

State Theory and Semiclassical Tunneling Calculations”, T. Joseph, R. Steckler,

and D. G. Truhlar, J. Chem. Phys. 87, 7036 (1987).

18. “Algorithms and Accuracy Requirements for Computing Reaction Paths by the

Method of Steepest Descent”, B. C. Garrett, M. J. Redmon, R. Steckler, D. G.

Truhlar, M. S. Gordon, K. K. Baldridge, and D. Bartol, J. Phys. Chem. 92, 1476

(1988).

19. “Calculation of Reaction Rates and Kinetic Isotope Effects for Dissociative Chemisorption of H2 and D2 on Ni(100), Ni(110) and Ni(111) Surfaces”, T. N.

Truong, G. Hancock, and D. G. Truhlar, Surface Science 214, 523 (1989).

20. “Ab Initio Reaction Paths and Direct Dynamics Calculations”, K. K. Baldridge, M.

S. Gordon, R. Steckler, and D. G. Truhlar, J. Phys. Chem. 93, 5107 (1989).

21. “Application of the Large-Curvature Tunneling Approximation to Polyatomic

Molecules: Abstraction of H or D by Methyl Radical”, B. C. Garrett, T. Joseph, T.

N. Truong, and D. G. Truhlar, Chem. Phys. 136, 271 (1989); erratum: 140, 207

(1990).

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22. “Transition State Structure, Barrier Height, and Vibrational Frequencies for the

Reaction Cl + CH4 → CH3 + HCl”, T. N. Truong, D. G. Truhlar, K. K. Baldridge,

M. S. Gordon, and R. Steckler, J. Chem. Phys. 90, 7137 (1989).

23. “Projection Operator Method for Geometry Optimization with Constraints”, D.-h.

Lu, M. Zhao, and D. G. Truhlar, J. Comp. Chem. 12, 376 (1991).

24. “A Simple Approximation for the Vibrational Partition Function of a Hindered

Internal Rotation”, D. G. Truhlar, J. Comp. Chem. 12, 266 (1991).

25. “The Definition of Reaction Coordinates for Reaction-Path Dynamics”, G. A.

Natanson, B. C. Garrett, T. N. Truong, T. Joseph, and D. G. Truhlar,

J. Chem. Phys. 94, 7875 (1991).

26. “Interpolated Variational Transition State Theory: Practical Methods for Estimating

Variational Transition State Properties and Tunneling Contributions to Chemical

Reaction Rates from Electronic Structure Calculations”, A. Gonzalez-Lafont, T. N.

Truong, and D. G. Truhlar, J. Chem. Phys. 95, 8875 (1991).

27. “Optimized Calculation of Reaction Paths and Reaction-Path Functions for

Chemical Reactions”, V. S. Melissas, D. G. Truhlar, and B. C. Garrett, J. Chem.

Phys. 96, 5758 (1992).

28. “Variational Transition-State Theory with Multidimensional, Semiclassical,

Ground-State Transmission Coefficients: Application to Secondary Deuterium

Kinetic Isotope Effects in Reactions Involving Methane and Chloromethane”, D. G.

Truhlar, D.-h. Lu, S. C. Tucker, X. G. Zhao, A. Gonzàlez-Lafont, T. N. Truong, D.

Maurice, Y-.P. Liu, and G. C. Lynch, ACS Symp. Series 502, 16 (1992).

29. “Polyrate 4: A New Version of a Computer Program for the Calculation of

Chemical Reaction Rates for Polyatomics”, D.-h. Lu, T. N. Truong, V. S. Melissas,

G. C. Lynch, Y.-P. Liu, B. C. Garrett, R. Steckler, A. D. Isaacson, S. N. Rai, G.

Hancock, J. G. Lauderdale, T. Joseph, and D. G. Truhlar, Comp. Phys. Comm. 71,

235 (1992).

30. “MORATE: A Program for Direct Dynamics Calculations of Chemical Reaction

Rates by Semiempirical Molecular Orbital Theory”, T. N. Truong, D.-h. Lu, G. C.

Lynch, Y.-P. Liu, V. S. Melissas, J. J. P. Stewart, R. Steckler, B. C. Garrett, A. D.

Isaacson, A. Gonzalez-Lafont, S. N. Rai, G. C. Hancock, T. Joseph, and D. G.

Truhlar, Comp. Phys. Comm. 75, 143 (1993).

31. “Molecular Modeling of the Kinetic Isotope Effect for the [1,5]-Sigmatropic

Rearrangement of cis-1,3-Pentadiene”, Y.-P. Liu, G. C. Lynch, T. N. Truong, D.-h.

Lu, and D. G. Truhlar, J. Amer. Chem. Soc. 115, 2408 (1993).

32. “Interpolated Variational Transition State Theory and Tunneling Calculations of the

Rate Constant of the Reaction OH + CH4 at 223-2400 K”, V. S. Melissas and D. G.

Truhlar, J. Chem. Phys. 99, 1013 (1993).

33. “Bond-Distance and Bond-Angle Constraints in Reaction-Path Dynamics

Calculations”, D.-h. Lu and D. G. Truhlar, J. Chem. Phys. 99, 2723 (1993).

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34. “Direct Dynamics Calculation of the Kinetic Isotope Effect for an Organic

Hydrogen-Transfer Reaction, Including Corner-Cutting Tunneling in 21

Dimensions”, Y.-P. Liu, D.-h. Lu, A. Gonzalez-Lafont, D. G. Truhlar, and B. C.

Garrett, J. Amer. Chem. Soc. 115, 7806 (1993).

35. “Effect of Phonon Coupling on Hydrogen Tunneling Rates at Gas-Surface

Interfaces”, S. E. Wonchoba and D. G. Truhlar, J. Chem. Phys. 99, 9637 (1993).

36. “Variational Transition State Theory and Semiclassical Tunneling Calculations with

Interpolated Corrections: A New Approach to Interfacing Electronic Structure

Theory and Dynamics for Organic Reactions”, W.-P. Hu, Y.-P. Liu, and D. G.

Truhlar, Faraday Trans. Chem. Soc. 90, 1715 (1994).

37. “Reaction Path Approaches to Dynamics at a Gas-Solid Interface: Quantum

Tunneling Effects for an Adatom on a Non-Rigid Metallic Surface”, S. E.

Wonchoba, W.-P. Hu, and D. G. Truhlar in Theoretical and Computational

Approaches to Interface Phenomena, edited by H. L. Sellers and J. T. Golab

(Plenum, New York, 1994), p. 1.

38. “Surface Diffusion of H on Ni(100). Interpretation of the Transition Temperature”,

S. E. Wonchoba, W.-P. Hu, and D. G. Truhlar, Phys. Rev. B 51, 9985 (1995).

39. “Polyrate 6.5: A New Version of Computer Program for the Calculation of

Chemical Reaction Rates for Polyatomics”, R. Steckler, W.-P. Hu, Y.-P. Liu, G. C.

Lynch, B. C. Garrett, A. D. Isaacson, V. S. Melissas, D.-h. Lu, T. N. Truong, S. N.

Rai, G. C. Hancock, J. G. Lauderdale, T. Joseph, and D. G. Truhlar, Computer

Physics Communications 88, 341 (1995).

40. “Direct Dynamics Method for the Calculation of Reaction Rates”, D. G. Truhlar, in

The Reaction Path in Chemistry: Current Approaches and Perspectives, edited by

D. Heidrich (Kluwer, Dordrecht, 1995), p. 229.

41. “Reaction-Path Potential and Vibrational Frequencies in Terms of Curvilinear

Internal Coordinates”, C. F. Jackels, Zhen Gu, and D. G. Truhlar, J. Chem. Phys.

102, 3188 (1995).

42. “Dual-Level Reaction Path Dynamics (The /// Approach to VTST with

Semiclassical Tunneling). Application to OH + NH3 → H2O + NH2 “ J.C.

Corchado, J. Espinosa-Garcia, W.-P. Wu, I. Rossi, and D. G. Truhlar, J. Phys.

Chem. 99, 687 (1995).

43. “Reaction-Path Dynamics in Curvilinear Internal Coordinates Including Torsions,”

K. A. Nguyen, C. F. Jackels, and D. G. Truhlar, J. Chem. Phys. 104, 6491 (1996).

44. “Improved Dual-Level Direct Dynamics Method for Reaction Rate Calculations

with Inclusion of Multidimensional Tunneling Effects and Validation for the Reaction of H with trans-N2H2” Y.-Y. Chuang, and D. G. Truhlar, J. Phys. Chem.

A 101, 3808 (1997); erratum: 101, 8741 (1997).

45. “Reaction-Path Dynamics with Harmonic Vibrational Frequencies in Curvilinear

Internal Coordinates: H + trans-N2H2 → H2 + N2H”, Y.-Y. Chuang and D. G.

Truhlar, J. Chem. Phys. 107, 83 (1997).

46. “Reaction Path Dynamics in Redundant Internal Coordinates,” Y.-Y. Chuang and

D. G. Truhlar, J. Phys. Chem. A 102, 242 (1998).

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47. “Variation Transition State Theory Without the Minimum-Energy Path,” J. Villà

and D. G. Truhlar, Theor. Chem. Acc. 97, 317 (1997).

48. “Mapped Interpolation Methods for Variational Transition State Theory,” J. C.

Corchado, E. L. Coitiño, Y.-Y. Chuang, P. L. Fast, D. G. Truhlar, J. Phys. Chem. A

102, 2424 (1998).

49. “Variational Reaction Path Algorithm,” P. L. Fast and D. G. Truhlar, J. Chem.

Phys. 109, 3721 (1998).

50. “The Calculation of Kinetic Isotope Effects Based on a Single Reaction Path,” P. L.

Fast, J. C. Corchado, and D. G. Truhlar, J. Chem. Phys. 109, 6237 (1998).

51. “Interface of Electronic Structure and Dynamics for Reactions in Solution,” Y.-Y.

Chuang, C. J. Cramer, and D. G. Truhlar, International Journal of Quantum

Chemistry 70, 887-896 (1998). (Sanibel issue) doi.org/10.1002/(SICI)1097-461X(1998)70:4/5<887::AID-QUA34>3.0.CO;2-W

52. “Mapped Interpolation Scheme for Single-Point Energy Corrections in Reaction

Rate Calculations and a Critical Evaluation of Dual-Level Reaction-Path Dynamics

Methods,” Y.-Y. Chuang, J. C. Corchado, and D. G. Truhlar, J. Phys. Chem. A 103,

1140 (1999).

53. “Statistical Thermodynamics of Bond Torsional Modes”, Y.-Y. Chuang and D. G.

Truhlar, J. Chem. Phys. 112, 1221 (2000); 121, 7036(E) (2004); 124, 0000(E)

(2006).

54. “Nonequilibrium Solvation Effects for a Polyatomic Reaction in Solution”, Y.-Y.

Chuang and D. G. Truhlar, J. Amer. Chem. Soc., 121, 10157 (1999).

55. “Improved Algorithm for Corner Cutting Calculations”, A. Fernandez-Ramos and

D. G. Truhlar, J. Chem. Phys. 114, 1491 (2001).

56. “Interpolated Algorithm for Large-Curvature Tunneling Calculations of

Transmission Coefficients for Variational Transition State Theory Calculations of

Reaction Rates”, A. Fernandez-Ramos, D. G. Truhlar, J. C. Corchado, and J.

Espinosa-Garcia, J. Phys. Chem. A 106, 4957 (2002).

57. "Tests of Potential Energy Surfaces for H + CH4 <-> CH3 + H2: Deuterium and

Muonium Kinetic Isotope Effects for the Forward and Reverse Reaction," J. Pu and

D. G. Truhlar, J. Chem. Phys. 117, 10675-10687 (2002).

58. "Efficient Molecular Mechanics for Chemical Reactions: Multiconfiguration

Molecular Mechanics using Partial Electronic Structure Hessians," H. Lin, J. Pu, T.

V. Albu, and D. G. Truhlar, J. Phys. Chem. A 108, 4112-4124 (2004).

59. "Temperature Dependence of Carbon-13 Kinetic Isotope Effects of Importance to

Global Climate Change," H. Lin, Y. Zhao, B. A. Ellingson, J. Pu, and D. G.

Truhlar, Journal of the American Chemical Society 127, 2830-2831 (2005).

60. "A New Algorithm for Efficient Direct Dynamics Calculations of Large- Curvature

Tunneling and Its Application to Radical Reactions with 9-15 Atoms," A.

Fernández-Ramos and D. G. Truhlar, Journal of Chemical Theory and Computation

1, 1063-1078 (2005).

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61. "Variational Transition State Theory," B. C. Garrett and D. G. Truhlar, in Theory

and Applications of Computational Chemistry: The First Forty Years, edited by C.

E. Dykstra, G. Frenking, K. S. Kim, and G. E. Scuseria (Elsevier, Amsterdam,

2005), pp. 67-87.

62. "Variational Transition State Theory and Multidimensional Tunneling for Simple

and Complex Reactions in the Gas Phase, Solids, Liquids, and Enzymes," D. G.

Truhlar, in Isotope Effects in Chemistry and Biology, edited by A. Kohen and H.-H.

Limbach (Marcel Dekker, Inc., New York, 2006), pp. 579-

620.http://t1.chem.umn.edu/Truhlar/docs/C71.pdf

63. "Statistical Thermodynamics of Bond Torsional Modes. Tests of Separable,

Almost-Separable and Improved Pitzer-Gwinn Approximations", B. A. Ellingson,

V. A. Lynch, S. L. Mielke, and D. G. Truhlar, Journal of Chemical Physics 125,

084305/1-17 (2006).

64. "Multidimensional Tunneling, Recrossing, and the Transmission Coefficient for

Enzymatic Reactions,” J. Pu, J. Gao, and D. G. Truhlar, Chemical Reviews 106,

3140-3169 (2006).

65. "Multi-Configuration Molecular Mechanics Based on Combined Quantum

Mechanical and Molecular Mechanical Calculations," H. Lin, Y. Zhao, O.

Tishchenko, and D. G. Truhlar, Journal of Chemical Theory and Computation 2,

1237-1254 (2006).

66. "Optimizing the Performance of the Multiconfiguration Molecular Mechanics

Method," O. Tishchenko and D. G. Truhlar, Journal of Physical Chemistry A 110,

13530-13536 (2006).

67. "Transition State Theory and Chemical Reaction Dynamics in Solution," D. G.

Truhlar and J. R. Pliego Jr., in Continuum Solvation Models in Chemical Physics:

Theory and Application, edited by B. Mennucci and R. Cammi (Wiley), submitted

Oct. 6, 2006.

68. "Modeling of Bimolecular Reactions," A. Fernández-Ramos, J. A. Miller, S. J.

Klippenstein, and D. G. Truhlar, Chemical Reviews 106, 4518-4584 (2006).

69. "Variational Transition State Theory in the Treatment of Hydrogen Transfer

Reactions, " D. G. Truhlar and B. C. Garrett, in Hydrogen Transfer Reactions,

edited by J. T. Hynes, J. P. Klinman, H. H. Limbach, and R. L. Schowen (Wiley-

VCH, Weinheim, Germany, 2007), Vol. 2, pp. 833-874.

70. "Hydrogen Atom Transfers in B12 Enzymes," R. Banerjee, D. G. Truhlar, A.

Dybala-Defratyka, P. Paneth, in Hydrogen Transfer Reactions, edited by J. T.

Hynes, J. P. Klinman, H.-H. Limbach, and R. L. Schowen (Wiley-VCH, Weinheim,

Germany, 2007), Vol. 4, pp. 1473-1495.

71. "Variational Transition State Theory with Multidimensional Tunneling," A.

Fernandez-Ramos, B. A. Ellingson, B. C. Garrett, and D. G. Truhlar, in Reviews in

Computational Chemistry, Vol. 23, edited by K. B. Lipkowitz and T. R. Cundari

(Wiley-VCH, Hoboken, NJ, 2007), pp. 125-232.

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72. "Global Potential Energy Surfaces with Correct Permutation Symmetry by Multi-

Configuration Molecular Mechanics," O. Tishchenko and D. G. Truhlar, Journal of

Chemical Theory and Computation 3, 938-948 (2007). doi.org/10.1021/ct600315h

73. "Symmetry Numbers and Chemical Reaction Rates," A. Fernández-Ramos, B. A.

Ellingson, R. Meana-Pañeda, J. M. C. Marques and D. G. Truhlar, Theoretical

Chemistry Accounts 118, 813-826 (2007). doi.org/10.1007/s00214-007-0328-0

74. "Multi-Coefficient Gaussian-3 Calculation of the Rate Constant for the OH + CH4

Reaction and its 12C/13C Kinetic Isotope Effect with Emphasis on the Effects of

Coordinate System and Torsional Treatment," B. A. Ellingson, J. Pu, H. Lin, Y.

Zhao, and D. G. Truhlar, Journal of Physical Chemistry A 111, 11706-11717

(2007). doi.org/10.1021/jp072843j

75. "Explanation of the Unusual Temperature Dependence of the Atmospherically

Important OH + H2S → H2O + SH Reaction and Prediction of the Rate Constant at

Combustion Temperatures," B. A. Ellingson, and D. G. Truhlar, Journal of the

American Chemical Society 129, 12765-12771 (2007). doi.org/10.1021/ja072538b

76. "Reactions of Hydrogen Atom with Hydrogen Peroxide," B. A. Ellingson, D. P.

Theis, O. Tishchenko, J. Zheng, and D. G. Truhlar, J. Phys. Chem. A 111, 13554-

13566 (2007). doi.org/10.1021/jp077379x

77. "Density Functional Study of Methyl Radical Association Reaction Kinetics," J.

Zheng, S. Zhang, and D. G. Truhlar, Journal of Physical Chemistry A 112, 11509-

11513 (2008). dx.doi.org/10.1021/jp806617m

78. "Mechanistic Analysis of the Base-Catalyzed HF Elimination from 4-Fluoro-4-(4'-

nitrophenyl)butane-2-one Based on Liquid-Phase Kinetic Isotope Effects Calculated

by Dynamics Modeling with Multidimensional Tunneling," Y. Kim, A. V.

Marenich, J. Zheng, K. H. Kim, M. Kołodziejska-Huben, M. Rostkowski, P.

Paneth, and D. G. Truhlar, Journal of Chemical Theory and Computation 5, 59-67

(2009). dx.doi.org/10.1021/ct800345j

79. "Critical Role of Substrate Conformational Change in the Proton Transfer Process

Catalyzed by 4-Oxalocrotonate Tautomerase," J. Ruiz-Pernía, M. Garcia-Viloca, S.

Bhattacharyay, J. Gao D. G. Truhlar, and I. Tuñon, Journal of the American

Chemical Society 131, 2687-2698 (2009). dx.doi.org/10.101/ja8087423

80. "Direct Dynamics Study of Hydrogen-Transfer Isomerization of 1-Pentyl and 1-

Hexyl Radicals," J. Zheng and D. G. Truhlar , Journal of Physical Chemistry A 113,

11919-11925 (2009). dx.doi.org/10.1021/jp903345x

81. "Phase Space Prediction of Product Branching Ratios: Canonical Competitive

Nonstatistical Model," J. Zheng, E. Papajak, and D. G. Truhlar, Journal of the

American Chemical Society 131, 15754-15760 (2009).

x.doi.org/10.1021/ja904405v

82. "Least-Action Tunneling Transmission Coefficient for Polyatomic Reactions," R.

Meana-Pañeda, D. G. Truhlar, and A. Fernández-Ramos, Journal of Chemical

Theory and Computation 6, 6-17 (2010). dx.doi.org/10.1021/ct900420e

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83. "Kinetics of Hydrogen-Transfer Isomerizations of Butoxyl Radicals," J. Zheng and D.

G. Truhlar, Physical Chemistry Chemical Physics 12, 7782-7793 (2010).

dx.doi.org/10.1039/b927504e.

84. “Free Energy Surfaces for Liquid-Phase Reactions and Their Use to Study the

Border Between Concerted and Nonconcerted -Elimination Reactions of Esters

and Thioesters,” Y. Kim, J. R. Mohrig, and D. G. Truhlar, Journal of the American

Chemical Society 131, 11071-11082 (2010). dx.doi.org/10.1021/ja101104q

85. “Computational Thermochemistry: Scale Factor Databases and Scale Factors for

Vibrational Frequencies Obtained from Electronic Model Chemistries,” I. M.

Alecu, J. Zheng, Y. Zhao, and D. G. Truhlar, Journal of Chemical Theory and

Computation 6, 2872-2887 (2010). dx.doi.org/10.1021/ct100326h.

86. “Direct Dynamics Implementation of the Least-Action Tunneling Transmission

Coefficient. Application to the CH4/CD3H/CD4+CF3 Abstraction Reactions,” R.

Meana-Pañeda, D. G. Truhlar, and A. Fernández-Ramos, Journal of Chemical

Theory and Computation 6, 3015-3025 (2010). dx.doi.org/10.1021/ct100285a

87. “Free Energy Surfaces for Liquid-Phase Reactions and Their Use to Study the

Border Between Concerted and Nonconcerted α,β-Elimination Reactions of Esters

and Thioesters,” Y. Kim, J. R. Mohrig, and D. G. Truhlar, Journal of the American

Chemical Society 132, 11071-11082 (2010). doi.org/10.1021/ja101104q

88. “High-Level Direct-Dynamics Variational Transition State Theory Calculations

Including Multidimensional Tunneling of the Thermal Rate Constants, Branching

Ratios, and Kinetic Isotope Effects of the Hydrogen Abstraction Reactions from

Methanol by Atomic Hydrogen,” R. Meana-Pañeda, D. G. Truhlar and A.

Fernández-Ramos, Journal of Chemical Physics 134, 094302/1-14 (2011).

dx.doi.org/10.1063/1.3555763

89. “Practical Methods for Including Torsional Anharmonicity in Thermochemical

Calculations of Complex Molecules: The Internal-Coordinate Multi-Structural

Approximation,” J. Zheng, T. Yu, E. Papajak, I, M. Alecu, S. L. Mielke, and D. G.

Truhlar, Physical Chemistry Chemical Physics 13, 10885-10907 (2011).

dx.doi.org/10.1039/C0CP02644A

90. “Multi-Structural Variational Transition State Theory. Kinetics of the 1,4-Hydrogen

Shift Isomerization of the Pentyl Radical with Torsional Anharmonicity,” T. Yu, J.

Zheng, and D. G. Truhlar, Chemical Science 2, 2199-2213 (2011).

dx.doi.org/10.1039/ C1SC00225B

91. “Computational Study of the Reactions of Methanol with the Hydroperoxyl and

Methyl Radicals. 2. Accurate Thermal Rate Constants,” I. M. Alecu and D. G.

Truhlar, Journal of Physical Chemistry A 115, 14599-14611 (2011).

dx.doi.org/10.1021/jp209029p

92. “Multipath Variational Transition State Theory. Rate Constant of the 1,4-Hydrogen

Shift Isomerization of the 2-Cyclohexylethyl Radical,” T. Yu, J. Zheng, and D. G.

Truhlar, Journal of Physical Chemistry A 116, 297-308 (2012).

dx.doi.org/10.1021/jp209146b

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93. “Kinetics of the Hydrogen Abstraction from Carbon-3 of 1-Butanol by

Hydroperoxyl Radical: Multi-Structural Variational Transition State Calculations of

a Reaction with 262 Conformations of the Transition State,” P. Seal, E. Papajak,

and D. G. Truhlar, Journal of Physical Chemistry Letters 3, 264-271 (2012).

dx.doi.org/10.1021/jz201546e

94. “Multi-Structural Variational Transition State Theory: Kinetics of the 1,5-Hydrogen

Shift Isomerization of 1-Butoxyl Radical Including All Structures and Torsional

Anharmonicity,” X. Xu, E. Papajak, J. Zheng, and D. G. Truhlar, Physical

Chemistry Chemical Physics 14, 4204-4216 (2012).

dx.doi.org/10.1039/c2cp23692c.

95. “Multi-path Variational Transition State Theory for Chemical Reaction Rates of

Complex Polyatomic Species: Ethanol + OH Reactions,” J. Zheng and D. G.

Truhlar, Faraday Discussions 157, 59-88 (2012). dx.doi.org/10.1039/C2FD20012K.

96. “MSTor: A program for calculating partition functions, free energies, enthalpies,

entropies, and heat capacities of complex molecules including torsional

anharmonicity,” J. Zheng, S. L Mielke, K. L Clarkson, and D. G. Truhlar, Computer

Physics Communications 183, 1803-1812 (2012).

dx.doi.org/10.1016/j.cpc.2012.03.007

97. “A Product Branching Ratio Controlled by Vibrational Adiabaticity and Variational

Effects: Kinetics of the H + trans-N2H2 Reactions,” J. Zheng, R. J. Rocha, M.

Pelegrini, L. F. A. Ferrão, E. F. V. Carvalho, O. Roberto-Neto, F. B. C. Machado,

and D. G. Truhlar, Journal of Chemical Physics 136, 184310/1-10 (2012).

dx.doi.org/10.1063/1.4707734

98. "Role of Conformational Structures and Torsional Anharmonicity in Controlling

Chemical Reaction Rates and Relative Yields: Butanal + HO2 Reactions," J. Zheng,

P. Seal, and D. G. Truhlar, Chemical Science 4, 200-212 (2013).

dx.doi.org/10.1039/c2sc21090h

99. "Multi-Structural Variational Transition State Theory: Kinetics of the Hydrogen

Abstraction from Carbon-2 of 2-Methyl-1-propanol by Hydroperoxyl Radical

Including All Structures and Torsional Anharmonicity," X. Xu, T. Yu, E. Papajak,

and D. G. Truhlar, Journal of Physical Chemistry A 116, 10480-10487 (2012).

dx.doi.org/10.1021/jp307504p

100. "Biofuel Combustion. Energetics and Kinetics of Hydrogen Abstraction from

Carbon-1 in n-Butanol by the Hydroperoxyl Radical Calculated by Coupled Cluster

and Density Functional Theories and Multi-Structural Variational Transition State

Theory with Multidimensional Tunneling," I. M. Alecu, J. Zheng, E. Papajak, T.

Yu, and D. G. Truhlar, Journal of Physical Chemistry A 116, 12206-12213 (2012).

dx.doi.org/10.1021/jp308460y

101. “Kinetics of the Hydrogen Atom Abstraction Reactions from 1-Butanol by

Hydroxyl Radical: Theory Matches Experiment and Then Some,” P. Seal, G.

Oyedepo, and D. G. Truhlar, Journal of Physical Chemistry A 117, 275-282 (2013).

dx.doi.org/10.1021/jp310910f

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102. “Quantum Thermochemistry: Multi-Structural Method with Torsional

Anharmonicity Based on a Coupled Torsional Potential,” J. Zheng and D. G.

Truhlar, Journal of Chemical Theory and Computation 9, 1356-1367 (2013).

dx.doi.org/10.1021/ct3010722

103. “Including Torsional Anharmonicity in Canonical and Microcanonical Reaction

Path Calculations,” J. Zheng and D. G. Truhlar, Journal of Chemical Theory and

Computation 9, 2875-2881(2013). dx.doi.org/10.1021/ct400231q

104. "MSTor version 2013: A new version of the computer code for the multistructural

torsional anharmonicity with a coupled torsional potential," J. Zheng, R. Meana-

Pañeda, and D. G. Truhlar, Computer Physics Communications 184, 2032-2033

(2013). [new version announcement] dx.doi.org/10.1016/j.cpc.2013.03.011

105. “Multi-Path Variational Transition State Theory for Chiral Molecules: The Site-

Dependent Kinetics for Abstraction of Hydrogen from Hydroperoxyl Radical,

Analysis of Hydrogen Bonding in the Transition State, and Dramatic Temperature

Dependence of the Activation Energy,” J. L. Bao, R. Meana-Pañeda, and D. G.

Truhlar, Chemical Science 6, 5866-5881 (2015). doi.org/10.1039/C5SC01848J

106. “Kinetics of Hydrogen Radical Reactions with Toluene by Chemical Activation

Theory Employing System-Specific Quantum RRK Theory Calibrated by

Variational Transition State Theory,” J. L. Bao, J. Zheng, and D. G. Truhlar,

Journal of the American Chemical Society 138, 2690-2704 (2016).

doi.org/10.1021/jacs.5b11938

107. “Silane-Initiated Nucleation in Chemically Active Plasmas: Validation of Density

Functionals, Mechanisms, and Pressure-Dependent Variational Transition State

Calculations,” J. L. Bao and D. G. Truhlar, Physical Chemistry Chemical Physics

18, 10097-10108 (2016). doi.org/10.1039/c6cp00816j

108. “Predicting Pressure-Dependent Unimolecular Rate Constants Using Variational

Transition State Theory with Multidimensional Tunneling Combined with System-

Specific Quantum RRK Theory: A Definitive Test for Fluoroform Dissociation,” J.

L. Bao, X. Zhang, and D. G. Truhlar, Physical Chemistry Chemical Physics 18,

16659-16670 (2016). doi.org/10.1039/C6CP02765B

109. “Atmospheric Chemistry of Criegee Intermediates. Unimolecular Reactions and

Reactions with Water,” B. Long, J. L. Bao, and D. G. Truhlar, Journal of the

American Chemical Society 138, 14409-14422 (2016).

doi.org/10.1021/jacs.6b08655

110. “Association of CF2 and Dissociation of C2F4 by Variational Transition State

Theory and System-Specific Quantum RRK Theory,” J. L. Bao, X. Zhang, and D.

G. Truhlar, Proceedings of the National Academy of Sciences U.S.A. 113, 13606-

13611 (2016). doi.org/10.1073/pnas.1616208113

111. “Computational Thermochemistry: Automated Generation of Scale Factors for

Vibrational Frequencies Calculated by Electronic Structure Model Chemistries," H.

S. Yu, L. J. Fiedler, I. M. Alecu, and D. G. Truhlar, Computer Physics

Communications 210, 132-138 (2017). doi.org/10.1016/j.cpc.2016.09.004

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112. “Reaction of SO2 with OH in the Atmosphere,” B. Long, J. L. Bao, and D. G.

Truhlar, Physical Chemistry Chemical Physics 19, 8091-8100 (2017).

doi.org/10.1039/c7cp00497d

113. “Dual-Level Method for Estimating Multi-Structural Partition Functions with

Torsional Anharmonicity,” J. L. Bao, L. Xing, and D. G Truhlar, Journal of

Chemical Theory and Computation 13, 2511-2522 (2017).

doi.org/10.1021/acs.jctc.7b00232

114. “Variational Transition State Theory: Theoretical Framework and Recent

Developments,” J. L. Bao and D. G. Truhlar, Chemical Society Reviews 46, 7548-

7596 (2017). doi.org/10.1039/C7CS00602K

115. “Kinetics of the Methanol Reaction with OH at Interstellar, Atmospheric, and

Combustion Temperature,” L. G. Gao, J. Zheng, A. Fernández-Ramos, D. G.

Truhlar, and X. Xu, Journal of the American Chemical Society 140, 2906-2918

(2018). doi.org/10.1021/jacs.7b12773

116. “Unimolecular Reaction of Acetone Oxide and its Reaction with Water in the

Atmosphere,” B. Long, J. L. Bao, and D. G. Truhlar, Proceedings of the National

Academy of Sciences U.S.A.115, 6135-6140 (2018).

doi.org/10.1073/pnas.1804453115

117. “Hydrogen Shift Isomerizations in the Kinetics of the Second Oxidation

Mechanism of Alkane Combustion. Reactions of the Hydroperoxypentylperoxy

OOQOOH Radical,” L. Xing, J. L. Bao, X. Wang, F. Zhang, and D. G. Truhlar,

Combustion and Flame Combustion and Flame 197, 88–101 (2018).

doi.org/10.1016/j.combustflame.2018.07.013

118. “Relative Rates of Hydrogen Shift Isomerizations Depend Strongly on Multiple-

Structure Anharmonicity,” L. Xing, J. L. Bao, Z. Wang, X. Wang, and D. G.

Truhlar, Journal of the American Chemical Society 140, 17556-17570 (2018).

doi.org/10.1021/jacs.8b09381

119. “Effect of Energy Dependence of the Density of States on Pressure-Dependent Rate

Constants,” J. L. Bao and D. G. Truhlar, Physical Chemistry Chemical Physics 20,

30475-30479 (2018). doi.org/10.1039/C8CP05915B

120. “Kinetics of the Strongly Correlated CH3O + O2 Reaction: The Importance of

Quadruple Excitations in Atmospheric and Combustion Chemistry,” B. Long, J. L.

Bao, and D. G. Truhlar, Journal of the American Chemical Society 141, 611-617

(2019). doi.org/10.1021/jacs.8b11766

121. “Kinetics of the Toluene Reaction with OH Radical,” R. M. Zhang, X. Xu, and D.

G. Truhlar, Research 2019, 5373785/1-19 (2019). (Research is the first journal in

the Science Partner Journal (SPJ) program and is the official journal of the China

Association for Science and Technology (CAST).) (Open access)

doi.org/10.34133/2019/5373785

122. “Rapid Unimolecular Reaction of Stabilized Criegee Intermediates and Implications

for Atmospheric Chemistry,” B. Long, J. L. Bao, and D. G. Truhlar, Nature

Communications 10, 2003/1-8 (2019). doi.org/10.1038/s41467-019-09948-7

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123. “Quantum Effects on H2 Diffusion in Zeolite RHO: Inverse Kinetic Isotope Effect

for Sieving,” L. G. Gao, R. M. Zhang, X. Xu, and D. G. Truhlar, Journal of the

American Chemical Society 134, 13635-13642 (2019).

doi.org/10.1021/jacs.9b06506

124. “Multistructural Anharmonicity Controls the Radical Generation Process in Biofuel

Combustion, L. Xing, Z. Wang, and D. G. Truhlar, Journal of the American

Chemical Society 141, 18531-18543 (2019). doi.org/10.1021/jacs.9b09194

125. “Association of Cl with C2H2 by Unified Variable-Reaction-Coordinate and

Reaction-Path Variational Transition State Theory,” L. Zhang, D. G. Truhlar,

and S. Sun, Proceedings of the National Academy of Sciences U.S.A. 117, 5610-

5616 (2020). doi.org/10.1073/pnas.1920018117

126. “Water Catalysis of the Reaction of Methanol with OH Radical in the Atmosphere

is Negligible,” J. Wu, L. G. Gao, Z. Varga, X. Xu, W. Ren, D. G Truhlar,

Angewandte Chemie International Edition 59, 10826-10830 (2020).

doi.org/10.1002/anie.202001065

127. “Large Anharmonic Effects on Tunneling and Kinetics: The Reaction of Propane

with Muonium.” L. Gao, D. G. Fleming, D. G. Truhlar, and X. Xu, Journal of

Physical Chemistry Letters 17, 4154-4159 (2021).

doi.org/10.1021/acs.jpclett.1c01229

128. “Strong dependence on multistructural anharmonicity of the relative rates of

intramolecular H-migration in alkylperoxyl and methylcyclohexylperoxyl radicals,”

L. Xing, L. Lian, and D. G. Truhlar, Combustion and Flame 231, 11503/1-12

(2021). doi.org/10.1016/j.combustflame.2021.111503

129. Atmospheric Kinetics. Bimolecular Reactions of Carbonyl Oxide by a Triple-Level

Strategy,” B. Long, Y. Wang, Y. Xia, X. He, J. L. Bao, and D. G. Truhlar, Journal

of the American Chemical Society 143, 8402-8413 (2021).

doi.org/10.1021/jacs.1c02029

22. ERRATA

All known errata to the GTST book chapter (Ref. 5 in Sect. 21) have been assembled into

a PDF file. This file is available at the Polyrate Web site.

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23. ACKNOWLEDGMENTS

The authors are grateful to Da-hong Lu, Thanh N. Truong, Sachchida N. Rai, Gene C.

Hancock, Jack Lauderdale, Tomi Joseph, Michael Zhen Gu, and Steven Clayton for

contributions to early versions of POLYRATE. The development of all versions of Polyrate

was supported in part by grants from the U. S. Department of Energy, Office of Basic

Energy Sciences (principal investigator: Donald G. Truhlar, University of Minnesota).

The development of versions 6.0-6.5 of Polyrate was also supported in part by a grant

from the National Science Foundation, Department of Advanced Scientific Computing

(principal investigator: Rozeanne Steckler, San Diego Supercomputer Center).

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24. INDEX

0IVTST KEYWORD DEFINITION ...................................................281

ABSORD SUBPROGRAM ......................................442

ACALC SUBPROGRAM ........................................442 ACESET SUBPROGRAM .......................................442 AITKEN SUBPROGRAM .......................................442 AITKF2 SUBPROGRAM .......................................442 AITKNF SUBPROGRAM .......................................442 ALFCT SUBPROGRAM .........................................442

ALLEXCIT KEYWORD DEFINITION ...................................................217 TESTRUN EXAMPLE ......................335, 340, 373

ANALYSIS KEYWORD DEFINITION ...................................................228

ANCOEF SUBPROGRAM ......................................442

ANGL SUBPROGRAM ..........................................442 ANGLCS SUBPROGRAM ......................................442 ANGLV SUBPROGRAM ........................................442 ANHARM SUBPROGRAM.............................. 62, 443 Anharmonicity .........................39, 40, 90, 91, 243 Anharmonicity keywords.................................163

ANHDER SUBPROGRAM .....................................443 ANTLR KEYWORD

DEFINITION ...................................................164 ARMUEF SUBPROGRAM .....................................443 ARMUEF1 SUBPROGRAM ...................................443 ARRSM SUBPROGRAM ........................................443

ARRSV SUBPROGRAM ........................................443 ASYMALP SUBPROGRAM ...................................443 ASYMCAL SUBPROGRAM ...................................443 ASYMENT SUBPROGRAM ...................................443 ASYMNZD SUBPROGRAM ...................................443 ASYMRMI SUBPROGRAM ...................................443

ATOMS KEYWORD............................... 71, 138, 299 DEFINITION ...................................................141

AVERJN SUBPROGRAM .......................................443 BANGLE1 SUBPROGRAM ....................................443 BARRI KEYWORD

DEFINITION ...................................................238

BATH KEYWORD DEFINITION ...................................................191

BCALC SUBPROGRAM ........................................444 BCALCO SUBPROGRAM ......................................444 BCALCP SUBPROGRAM ......................................444 BIMAT SUBPROGRAM .........................................444

BMAT SUBPROGRAM ..........................................444 BMAT1 SUBPROGRAM ........................................444 BMAT2 SUBPROGRAM ........................................444 BMAT5 SUBPROGRAM ........................................444 BMAT5X SUBPROGRAM .....................................444 BOLTZ SUBPROGRAM .........................................445

BOTHK KEYWORD DEFINITION ...................................................228

BRENT SUBPROGRAM ........................................ 445 BRNULI SUBPROGRAM ...................................... 445 BTEN1 SUBPROGRAM ........................................ 444

BTEN2 SUBPROGRAM ........................................ 445 BTEN5 SUBPROGRAM ........................................ 445 BTEN5X SUBPROGRAM ...................................... 445 BTENS SUBPROGRAM ........................................ 445 BTENTR SUBPROGRAM ...................................... 445 BTORSN SUBPROGRAM ...................................... 444

CALCS SUBPROGRAM ........................................ 445 CALCUB SUBPROGRAM ..................................... 445 Canonical order .................................................. 38 Canonical Variational Theory ........................... 15 CARTRP KEYWORD

DEFINITION................................................... 191

CASE SUBPROGRAM .......................................... 445 CD-SCSAG ............................................................ 48 CENTER SUBPROGRAM ................................ 62, 446 CENTR1 SUBPROGRAM ...................................... 446 CENTRAL SUBPROGRAM ................................... 446 CFLOAT SUBPROGRAM ...................................... 446

ch3tr1 test run................................................... 434 ch4cltr1 test run................................................ 426 ch4cltr2 test run................................................ 427 ch4ohtr1 test run ............................. 422, 424, 425 ch4ohtr2 test run .............................................. 423 ch4otr1 test run ................................................ 428

ch5fu29tr1 test run ........................................... 348 ch5fu29tr2 test run ........................................... 349 ch5fu30tr1 test run ........................................... 350 ch5fu30tr2 test run ........................................... 351 ch5fu30tr3 test run ........................................... 352 ch5fu30tr4 test run ........................................... 353

ch5fu30tr5 test run ........................................... 354 ch5fu30tr6 test run ........................................... 355 ch5fu31tr1 test run ........................................... 356 ch5fu40tr1 test run ........................................... 357 ch5fu40tr2 test run ........................................... 358 ch5fu40tr3 test run ........................................... 359

ch5fu40tr4 test run ........................................... 360 ch5fu40tr5 test run ........................................... 361 ch5fu40tr6 test run ........................................... 363 ch5fu50tr1 test run ........................................... 364 ch5fu50tr2 test run ........................................... 365 ch5fu50tr3 test run ........................................... 366

ch5fu51tr1 test run ........................................... 367 ch5icfu30tr1 test run ........................................ 368 ch5icfu30tr2 test run ........................................ 369 ch5icfu31tr1 test run ........................................ 370 ch5icfu40tr1 test run ........................................ 371 ch5icfu40tr2 test run ........................................ 372

ch5j1tr1 test run ............................................... 329 ch5j1tr10 test run ............................................. 340

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ch5j1tr11 test run..............................................341 ch5j1tr2 test run ................................................331 ch5j1tr3 test run ................................................332 ch5j1tr4 test run ................................................333

ch5j1tr5 test run ................................................334 ch5j1tr6 test run ................................................335 ch5j1tr7 test run ................................................336 ch5j1tr8 test run ................................................337 ch5j1tr9 test run ................................................338 ch5j2itr1 test run...............................................346

ch5j2itr2 test run...............................................347 ch5j2tr1 test run ................................................342 ch5j2tr2 test run ................................................344 ch5j2tr3 test run ................................................345 CHAIN UTILITY SUBPROGRAMS ........................... 73 CHARMMRATE ..................................................... 18

CHECK KEYWORD DEFINITION ...................................................141

CHKFRE SUBPROGRAM ......................................446 CHKUP SUBPROGRAM ........................................446 CLASS SUBPROGRAM .........................................446 CLASSVIB KEYWORD

DEFINITION ...................................................141 clhbrtr1 test run.................................................373 clhbrtr2 test run.................................................375 clhbrtr3 test run.................................................376 clhbrtr4 test run.................................................377 cmctr1 test run ..................................................379

cmctr2 test run ..................................................380 cmctr3 test run ..................................................381 CMS SUBPROGRAM ............................................446 COG SUBPROGRAM ............................................446 COHBT1 SUBPROGRAM ......................................446 COHBT2 SUBPROGRAM ......................................446

COLSHF SUBPROGRAM .......................................446 comp_pot.jc ......................................................502 comp_src.jc .......................................................503 COMT .............................................................50, 52 configure ...........................................................501 CONOUT SUBPROGRAM .....................................447

CONSTANT KEYWORD DEFINITION ...................................................164

CONV40 SUBPROGRAM ......................................447 Conventional Transition State Theory .............. 15 COORD KEYWORD

DEFINITION ...................................................192

COORD UTILITY SUBPROGRAMS .......................... 72 Coordinates

Cartesian ........................................................ 43 Curvilinear ..................................................... 43 Rectilinear ...................................................... 43

CORTRM SUBPROGRAM .....................................447

COSINE SUBPROGRAM .......................................447 CROSSPROD SUBPROGRAM ................................447 CRVVEC SUBPROGRAM ......................................447 CUBIC SUBPROGRAM .........................................447

CUBIC2 SUBPROGRAM ....................................... 447 CUBST SUBPROGRAM ........................................ 447 CURV KEYWORD

DEFINITION................................................... 192

DGRAD OPTION............................................. 101 TESTRUN EXAMPLE329, 334, 338, 373, 375,

383, 384 DHESS OPTION .............................................. 101

TESTRUN EXAMPLE ................................. 336 TESTRUN EXAMPLE ................................. 333

ONESIDE OPTION .......................................... 101 TESTRUN EXAMPLE ................................. 397

CUS KEYWORD DEFINITION................................................... 228

CUSSPL SUBPROGRAM ....................................... 447 CVCOOR SUBPROGRAM ..................................... 447

CVT ...................................................................... 28 TESTRUN EXAMPLE ...................................... 334

CVT KEYWORD DEFINITION................................................... 228 TEST RUN EXAMPLE .............................329, 338 TESTRUN EXAMPLE ..............................333, 337

CVT/MEPSAG ....................................................... 50 cwmctr1 test run............................................... 382 cwmctr2 test run............................................... 383 cwmctr3 test run............................................... 384 D parameter ...................................................... 164 DATTIM SUBPROGRAM ...................................... 447

DAXPY SUBPROGRAM ....................................... 447 DDOT SUBPROGRAM .......................................... 450 DEFALT SUBPROGRAM ...................................... 447 DEFENG SUBPROGRAM ...................................... 448 DEFGEN SUBPROGRAM ...................................... 448 DEFLT40 SUBPROGRAM .................................... 448

DEFOPT SUBPROGRAM ...................................... 448 DEFPAT SUBPROGRAM ...................................... 448 DEFRAT SUBPROGRAM ...................................... 448 DEFSEC SUBPROGRAM ...................................... 448 DEFSTA SUBPROGRAM ...................................... 448 DEFTUN SUBPROGRAM ...................................... 448

DELEX1 KEYWORD DEFINITION................................................... 239

DELTA2 KEYWORD ........................................ 42, 99 DELTA2 PARAMETER ......................................... 193 DELTAE KEYWORD

DEFINITION................................................... 239

DEMIN KEYWORD DEFINITION................................................... 164

DERIV2 SUBPROGRAM ....................................... 448 DERV SUBPROGRAM .......................................... 448 DERV24 SUBPROGRAM ...................................... 448 DERVAG SUBPROGRAM ..................................... 448

DETMI KEYWORD .............................................. 491 DEFINITION................................................... 281 TESTRUN EXAMPLE ...................................... 393

detmi utility program ....................................... 491

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DFGN31 SUBPROGRAM ......................................448 DGAMMA SUBPROGRAM ....................................449 DGEDI SUBPROGRAM .........................................449 DGEFA SUBPROGRAM ........................................449

DIATOM KEYWORD .............................................. 62 DEFINITION ...................................................165

DIATOM SUBPROGRAM ............................... 62, 449 DIFFD KEYWORD............................................42, 99 DIFFD PARAMETER ............................................193 DIGISTR SUBPROGRAM ......................................449

DIST SUBPROGRAM ............................................449 DL KEYWORD .....................................................102

DEFINITION ...................................................142 DLX2 KEYWORD

DEFINITION ...................................................156 DLX3 KEYWORD

DEFINITION ...................................................193 DOGLEG SUBPROGRAM ......................................449 DOPNM SUBPROGRAM .......................................449 DOREPR SUBPROGRAM ......................................449 DOREST SUBPROGRAM ......................................449 DORODS SUBPROGRAM ......................................449

DORPH SUBPROGRAM ........................................450 DOSAFR SUBPROGRAM ......................................450 DOSAGE SUBPROGRAM ......................................450 DOTPRD SUBPROGRAM ......................................450 DPMPAR SUBPROGRAM ......................................449 DPR123 SUBPROGRAM .......................................450

DPSWAP SUBPROGRAM ......................................450 DQQP KEYWORD

DEFINITION ...................................................165 RELATED KEYWORDS ...................................171

DSCAL SUBPROGRAM ........................................450 DSWAP SUBPROGRAM ........................................450

dumpot.f ........................................................71, 81 E1GEOM SECTION

DEFINITION ...................................................237 E1GRAD SECTION

DEFINITION ...................................................237 E1HESS SECTION

DEFINITION ...................................................237 EACT KEYWORD

DEFINITION ...................................................229 TESTRUN EXAMPLE .............................. 329, 338

EBND SUBPROGRAM ..........................................450 ECKARS SUBPROGRAM ......................................450

ECKART SUBPROGRAM ......................................450 ECKRT SUBPROGRAM ........................................450 EDGEOK KEYWORD

DEFINITION ...................................................229 EFFBATH SUBPROGRAM.....................................451 EFMAIN SUBPROGRAM .......................................451

EFOPT KEYWORD DEFINITION ...................................................156

EFORMD SUBPROGRAM .....................................451 EFOVLP SUBPROGRAM .......................................451

EFPHES SUBPROGRAM ....................................... 451 EHOOK SUBPROGRAM ................................. 78, 450 EIGENVECTOR KEYWORD

DEFINITION................................................... 166

ELEC KEYWORD DEFINITION................................................... 166

electronic structure input ............ 16, 63, 408, 416 Electronic structure input file

anharmonicities ............................................. 82 data interpolation .......................................... 85

Dummy potential energy surface ........... 71, 81 frequencies .................................................... 82 moment of inertia .......................................... 82 unit fu30 ................................................ 81, 241 unit fu40 ........................................................ 81 user-supplied information ............................ 83

ELLIP SUBPROGRAM .......................................... 451 ELRPH SUBPROGRAM ........................................ 451 EMIN KEYWORD

DEFINITION................................................... 217 ENDRODS SUBPROGRAM ................................... 451 ENDSLP SUBPROGRAM ...................................... 451

ENERGETICS SECTION ...............................148, 302 ENERGY KEYWORD

DEFINITION................................................... 167 ENERXN KEYWORD

DEFINITION................................................... 281 ENESAD KEYWORD

DEFINITION................................................... 281 ENORM SUBPROGRAM ....................................... 451 ENROUT SUBPROGRAM ..................................... 451 EPART SUBPROGRAM ........................................ 451 EPARTI SUBPROGRAM ....................................... 451 Equilibrium constant.......................................... 51

ERF SUBPROGRAM ............................................. 451 ES1 KEYWORD

DIFFD PARAMETER TESTRUN EXAMPLE ................................. 337

ES1 KEYWORD DELTA2 PARAMETER

TESTRUN EXAMPLE ................................. 337 METHOD DESCRIPTION ................................... 99 METHOD DESCRIPTION ................................... 42 TESTRUN EXAMPLE ...................................... 337

ES1 KEYWORD TESTRUN EXAMPLE ...................................... 342

ES1 KEYWORD TESTRUN EXAMPLE ...................................... 398

ES1OPT KEYWORD DEFINITION................................................... 193

ESD KEYWORD .............................................. 62, 99 TESTRUN EXAMPLE ..................... 333, 345, 391

Euler stabilization method................................. 42 Euler steepest-descents (ESD)method.............. 41 EVIB SUBPROGRAM ........................................... 452 EWKB SUBPROGRAM ......................................... 452

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EXCITED KEYWORD DEFINITION ...................................................217

EXFIRST KEYWORD.............................................. 89 DEFINITION ...................................................193

TESTRUN EXAMPLE .............................. 385, 396 Expert users ............................................. 321, 322 EXPND SUBPROGRAM ........................................452 EXSECOND KEYWORD ......................................... 89

DEFINITION ...................................................195 TESTRUN EXAMPLE .......................................385

EXTRAP SUBPROGRAM ......................................452 EXTRP SUBPROGRAM .........................................452 EXTRP40 SUBPROGRAM .....................................452 EZERO KEYWORD................................................. 69

CALCULATE OPTION TESTRUN EXAMPLE ......................... 373, 396

DEFINITION ...................................................149 READ OPTION

TESTRUN EXAMPLE ..................................375 EZUNIT KEYWORD

DEFINITION ...................................................149 F1DI SUBPROGRAM ............................................452

F1DIM SUBPROGRAM .........................................452 FACORD SUBPROGRAM ......................................452 FCINPT SUBPROGRAM ........................................452 FCMEP SUBPROGRAM ........................................452 FCN SUBPROGRAM .............................................452 FCRATE SUBPROGRAM .......................................452

FCSCALE KEYWORD DEFINITION ...................................................195

FCSCL SUBPROGRAM .........................................452 FDIAG SUBPROGRAM .........................................453 FDIAG2 SUBPROGRAM .......................................453 FDJAC1 SUBPROGRAM .......................................453

FICLSE SUBPROGRAM ........................................453 File fu30 input

lopt options ..................................................241 File usage ..........................................................505 findb utility program ........................................497

testrun example............................................380

FINDL SUBPROGRAM..........................................453 findl utility program .........................................497

testrun example............................................380 FINDLV SUBPROGRAM .......................................453 FINOUT SUBPROGRAM .......................... 51, 64, 453 FIOPEN SUBPROGRAM ........................................453

FIRSTSTEP KEYWORD ........................................100 CUBIC OPTION

TESTRUN EXAMPLE .................396, 398, 401 DEFINITION ...................................................196 RELATED KEYWORD .....................................193

FITMAX SUBPROGRAM .......................................453

FITMX SUBPROGRAM .........................................453 FIVFT SUBPROGRAM ..........................................454 FIVPT SUBPROGRAM ..........................................454 FORMA SUBPROGRAM .......................................454

FORMBT SUBPROGRAM ..................................... 454 FORMF SUBPROGRAM........................................ 454 FORMF2 SUBPROGRAM ..................................... 454 FORMG SUBPROGRAM ....................................... 454

FORWARDK KEYWORD DEFINITION................................................... 229 TESTRUN EXAMPLE ..............................385, 386

FPRINT KEYWORD DEFINITION................................................... 152

FREQ KEYWORD

DEFINITION................................................... 167 FREQIMAG KEYWORD

DEFINITION................................................... 283 FREQMAT KEYWORD ......................................... 103

DEFINITION................................................... 282 TESTRUN EXAMPLE ..............................380, 393

FREQSCALE KEYWORD DEFINITION................................................... 197

FREQUNIT KEYWORD DEFINITION................................................... 167

FRPRMN SUBPROGRAM ..................................... 454 FRSORT SUBPROGRAM ...................................... 454

GAMESSPLUSRATE .............................................. 18 GAUSQD SUBPROGRAM ..................................... 454 GAUSSQ SUBPROGRAM ..................................... 454 GAUSSRATE ......................................................... 18 GBSLVE SUBPROGRAM ...................................... 454 GBTQL2 SUBPROGRAM ...................................... 454

GCOMP KEYWORD DEFINITION ................................................... 156

GEMM SUBPROGRAM ........................................ 455 GENERAL SECTION ....................................138, 298 Generalized transition state theory ................... 28

Canonical variational theory (CVT)........ 28, 31

Microcanonical variational theory (µVT) ..... 28 GENSEC40 SUBPROGRAM .................................. 455 GEOM KEYWORD ................................................. 69

DEFINITION................................................... 167 Geometry optimization keywords

Polyrate ....................................................... 155

GETFRQ SUBPROGRAM ...................................... 455 GFDIAG SUBPROGRAM ...................................... 455 GHOOK SUBPROGRAM ................................. 78, 455 GIVTST SUBPROGRAM ....................................... 455 GRAD SUBPROGRAM ......................................... 455 GRADDR SUBPROGRAM ..................................... 455

GSETA SUBPROGRAM ........................................ 455 GSETM SUBPROGRAM ........................................ 455 GSETP SUBPROGRAM ......................................... 455 GSPEC KEYWORD

DEFINITION................................................... 229 TESTRUN EXAMPLE ...................................... 400

GTEMP KEYWORD DEFINITION................................................... 229 TESTRUN EXAMPLE ...................................... 397

GTLOG KEYWORD

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DEFINITION ...................................................230 GTST Book Chapter .......................................... 26 h2nitr1 test run..................................................421 h3o2fu31tr1 test run ............... 435, 436, 437, 438

h3tr1 test run .....................................................385 h3tr2 test run .....................................................386 h3tr3 test run .....................................................387 h3tr4 test run .....................................................388 HARMONIC KEYWORD

DEFINITION ...................................................168

HBT SUBPROGRAM .............................................456 HEADR SUBPROGRAM ........................................456 HESS KEYWORD

DEFINITION ...................................................197 HESSCAL KEYWORD

DEFINITION ...................................................152

HESSIAN KEYWORD DEFINITION ...................................................168

HHOOK SUBPROGRAM ................................ 78, 456 HINDERED ROTOR .92, 96, 97, 172, 173, 176, 282,

285, 383, 384, 425, 456, 493 HINDRT SUBPROGRAM .......................................456

HINDRT1 SUBPROGRAM .....................................456 hnitr1 test run ....................................................420 ho2tr1 test run ...................................................389 ho2tr2 test run ...................................................390 ho2tr3 test run ...................................................391 ho2tr4 test run ...................................................392

ho2tr5 test run ...................................................393 HQSC SUBPROGRAM ..........................................456 HREC KEYWORD

DEFINITION ...................................................157 HRMI KEYWORD.................................................493

DEFINITION ...................................................282

hrotor utility program .......................................493 HRPART SUBPROGRAM ......................................456 HRSET SUBPROGRAM .........................................456 HVAL SUBPROGRAM ..........................................456 HYBRD SUBPROGRAM ........................................456 HYBRD1 SUBPROGRAM ......................................456

ICFDIAG SUBPROGRAM ......................................456 ICFDRP SUBPROGRAM ........................................456 ICINT SUBPROGRAM ..........................................457 ICL KEYWORD ....................................................103 ICODAL SUBPROGRAM .......................................457 ICOPOT KEYWORD .............................................102

ICOUTRP SUBPROGRAM .....................................457 ICR KEYWORD....................................................103 ICSAVE SUBPROGRAM .......................................457 ICSVRP SUBPROGRAM ........................................457 ICVT

TESTRUN EXAMPLE ......................333, 334, 345

ICVT KEYWORD TEST RUN EXAMPLE ............................. 329, 338

IDAMAX SUBPROGRAM ......................................457 IDIRECT KEYWORD

DEFINITION................................................... 198 ILCT ................................................................... 58 IMODULE FILES

AAMOD.F90 .................................................. 488

IMOM40 SUBPROGRAM ..................................... 457 INCLUDE FILES .................................................. 441

PARAM.INC ................................................... 505 INERTA SUBPROGRAM ....................................... 458 INH KEYWORD ..................................................... 62

DEFINITION................................................... 198

TESTRUN EXAMPLE ..............................337, 385 INI KEYWORD

DEFINITION................................................... 198 INITGEO KEYWORD

DEFINITION................................................... 168 INITZE SUBPROGRAM ........................................ 458

INPUNIT KEYWORD DEFINITION................................................... 144

Input file fu29 ....................................................... 236 file fu30 ................................................. 81, 241 file fu31 ....................................................... 251

file fu40 ....................................................... 261 file fu5 ......................................................... 135

section descriptions........................137, 298 file fu50 ....................................................... 279 file fu51 ....................................................... 291

INTAB SUBPROGRAM ......................................... 458

INTABS SUBPROGRAM ....................................... 458 INTCOR SUBPROGRAM ...................................... 457 INTDEF KEYWORD

DEFINITION................................................... 198 INTEGR SUBPROGRAM ....................................... 458 INTERPOLATED OPTIMIZED CORRECTIONS

(VTST-IOC)......................................... 56, 102 INTERPOLATED VTST ...................................... 52 INTERSC SUBPROGRAM ..................................... 457 INTEUL SUBPROGRAM ....................................... 458 INTF31 SUBPROGRAM ....................................... 457 INTFNC SUBPROGRAM ....................................... 458

INTMU KEYWORD DEFINITION................................................... 199

INTPM SUBPROGRAM ........................................ 458 INTPM2 SUBPROGRAM ...................................... 458 INTRPL SUBPROGRAM ....................................... 458 INTRVL SUBPROGRAM ....................................... 457

INVRT1 SUBPROGRAM ....................................... 457 INVRT2 SUBPROGRAM ....................................... 457 INVRT3 SUBPROGRAM ....................................... 458 IOCOPT KEYWORD

DEFINITION................................................... 143 TESTRUN EXAMPLE ...................................... 380

ZERO OPTION TESTRUN EXAMPLE ................ 422, 424, 425

IRCX SUBPROGRAM ........................................... 459 IRFTG0 SUBPROGRAM ....................................... 459

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IRPH SUBPROGRAM ............................................459 IRPHZ SUBPROGRAM ..........................................459 Isoinertial coordinates ..................................38, 62 ISWAP SUBPROGRAM .........................................459

ISWP KEYWORD DEFINITION ...................................................199

ISWR KEYWORD DEFINITION ...................................................199

IVTMA SUBPROGRAM ........................................459 IVTMD SUBPROGRAM ........................................459

IVTMH SUBPROGRAM ........................................459 IVTST SECTION

DEFINITION ...................................................238 IVTST0 KEYWORD................................................ 53

DEFINITION ...................................................144 IVTST0 SUBPROGRAM ........................................459

IVTST0FREQ KEYWORD DEFINITION ...................................................202

IVTST0FREQ KEYWORD INCOMPATABILITY................................202

IVTST1 KEYWORD................................................ 53 DEFINITION ...................................................144

IVTST-M ............................................................... 54 IVTST-M ..........................................................109 IVTSTMOPT KEYWORD

DEFINITION ...................................................200 JACSCF SUBPROGRAM .......................................459 JAGUARATE.......................................................... 18

KAPA SUBPROGRAM ..........................................459 KAPPAS SUBPROGRAM .......................................459 KAPVA SUBPROGRAM ................................. 64, 459 KG1 SUBPROGRAM ............................................460 Large-curvature Tunneling ..........................15, 35 LCG3 ..............................................................35, 48

LCG3 SUBPROGRAM ...........................................460 LCG4 ..............................................................35, 48 LCGIT SUBPROGRAM..........................................460 LCGSRT SUBPROGRAM .......................................460 LCGTH SUBPROGRAM ........................................460 LCNORM SUBPROGRAM .....................................460

LCNWTN SUBPROGRAM .....................................460 LCPATH SUBPROGRAM ......................................460 LCPROB SUBPROGRAM ......................................460 LCPROJ SUBPROGRAM .......................................461 LCSET SUBPROGRAM .........................................461 LCSINT SUBPROGRAM ........................................461

LCSTX SUBPROGRAM .........................................461 LCT3 KEYWORD

DEFINITION ...................................................217 LCT4...................................................................116 LCT4 KEYWORD

DEFINITION ...................................................217

LCTCOR KEYWORD DEFINITION ...................................................283

LCTDETAIL KEYWORD DEFINITION ...................................................218

OUTPUT DETAILS .......................................... 309 LCTOPT KEYWORD

DEFINITION................................................... 218 INTERPOLATE OPTION

TESTRUN EXAMPLE ................................. 375 TESTRUN EXAMPLE .....329, 334, 335, 338, 340

LCTP SUBPROGRAM ........................................... 461 LCVCOR SUBPROGRAM ..................................... 461 LCVIB SUBPROGRAM ......................................... 461 LCVMOD SUBPROGRAM .................................... 461

LCXINT SUBPROGRAM ....................................... 461 LCXTAU SUBPROGRAM ..................................... 461 LCZCRT SUBPROGRAM ...................................... 462 LIN SUBPROGRAM ............................................. 462 LIN2 SUBPROGRAM ........................................... 462 LINAXIS KEYWORD

DEFINITION................................................... 169 LININT SUBPROGRAM ........................................ 462 link_exe.jc ........................................................ 504 LINMN SUBPROGRAM ........................................ 462 LINMR SUBPROGRAM ........................................ 462 LOCATE SUBPROGRAM ...................................... 462

LOCS SUBPROGRAM .......................................... 462 LOPT OPTIONS ................................................... 241 LOPT40 SUBPROGRAM ...................................... 462 LOWFREQ KEYWORD

DEFINITION................................................... 283 LSAME SUBPROGRAM ........................................ 462

LUBKSB SUBPROGRAM ...................................... 462 LUDCMP SUBPROGRAM ..................................... 462 MAIN SUBPROGRAM .......................................... 462 Manuals .............................................................. 25 MATINV SUBPROGRAM...................................... 463 MATX SUBPROGRAM ......................................... 463

MC-TINKERATE ................................................... 18 MDMOVIE KEYWORD

DEFINITION................................................... 144 MEPINV SUBPROGRAM ...................................... 463 MEPOUT SUBPROGRAM ..................................... 463 MEPSAG ......................................................... 35, 48

MEPSRT SUBPROGRAM ...................................... 463 MEPTYPEP KEYWORD........................................ 102

DEFINITION................................................... 284 TESTRUN EXAMPLE ..............................380, 393

MEPTYPER KEYWORD ....................................... 102 DEFINITION................................................... 284

TESTRUN EXAMPLE ..............................380, 393 MF DIVIDING SURFACE.............................125, 131 microcanonical optimized multidimensional

tunneling ........................................................ 15 MICROCANONICAL Variational Theory ............ 15 MINIMUM ENERGY PATH (MEP)

CALCULATING ................................................ 41 MIRP KEYWORD

DEFINITION................................................... 285 MITS KEYWORD

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DEFINITION ...................................................285 MNBRAK SUBPROGRAM .....................................463 MODULE FILES..................................................488

ALLOC.F90 ....................................................488

MOPAC program .................................................. 18 MOPEG SUBPROGRAM ........................................463 MOPHES SUBPROGRAM ......................................463 MOPOPT SUBPROGRAM ......................................463 MOPSET SUBPROGRAM ......................................463 MORATE ............................................................... 18

MORMODEL KEYWORD ........................................ 90 DEFINITION ...................................................169 MORSEI OPTION

TEST RUN EXAMPLE ....... 429, 430, 431, 432 TESTRUN EXAMPLE ........ 389, 390, 392, 397

MORSEIIIA OPTION

TEST RUN EXAMPLE .................................385 RELATED KEYWORDS .......................... 169, 170

MORSE KEYWORD ................................................ 90 DEFINITION ...................................................169 RELATED KEYWORDS ...................................169 TESTRUN EXAMPLE .... 385, 389, 390, 392, 429,

430, 431, 432 MORSEQQ KEYWORD ........................................... 90

DEFINITION ...................................................170 RELATED KEYWORDS .......................... 164, 169 TESTRUN EXAMPLE .......................................397

MUCDSC SUBPROGRAM .....................................463

MULTILEVELRATE ............................................... 18 MUSC SUBPROGRAM ..........................................464 MUSCCD SUBPROGRAM .....................................464 MUVT KEYWORD

DEFINITION ...................................................230 MUVTOPT KEYWORD

DEFINITION ...................................................231 TESTRUN EXAMPLE .............................. 389, 390

MXLNEQ SUBPROGRAM .....................................464 NATOMS VARIABLE ............................................. 70 NEARW SUBPROGRAM .......................................464 NEWT SUBPROGRAM ................................... 62, 464

NEXTPT KEYWORD DEFINITION ...................................................203

NEXTPT SUBPROGRAM .......................................464 nh3tr1 test run ...................................................394 nh3tr2 test run ...................................................395 NITER KEYWORD

DEFINITION ...................................................157 NOALLEXCIT KEYWORD

TESTRUN EXAMPLE .......................................386 NOCVT KEYWORD

TESTRUN EXAMPLE .......................................382 NONLINEAR KEYWORD

TESTRUN EXAMPLE .............................. 385, 429 NOOPT KEYWORD

TESTRUN EXAMPLE......................389, 390, 391 NOPROJECT KEYWORD

TESTRUN EXAMPLE ...................................... 398 NORMOD SUBPROGRAM ........................62, 63, 464 NOROUT SUBPROGRAM ..................................... 464 NOSADDLE KEYWORD ......................................... 44

NOST31 SUBPROGRAM ...................................... 464 NQE PARAMETER ............................................... 222 NQTH ................................................................... 49 NQTH PARAMETER ............................................ 222 NSEG2 .................................................................. 49 NSEGBOLTZ KEYWORD

TESTRUN EXAMPLE ...................................... 385 NSEGHETA KEYWORD

TESTRUN EXAMPLE ...................................... 385 NSTATE SUBPROGRAM ...................................... 464 NSTEPS KEYWORD

DEFINITION................................................... 204

NUMFRQ SUBPROGRAM ..................................... 464 NUMSTEP KEYWORD ........................................... 99

DEFINITION................................................... 152 RELATED KEYWORDS................................... 153

NUMTYP KEYWORD............................................. 98 DEFINITION................................................... 153

NWCHEMRATE..................................................... 18 OBTSRT SUBPROGRAM ...................................... 464 oh3fu30tr1 testrun............................................ 406 oh3fu30tr2 testrun............................................ 407 oh3fu30tr3 testrun............................................ 408 oh3fu30tr4 testrun............................................ 409

oh3fu30tr5 testrun............................................ 410 oh3fu30tr6 test run........................................... 411 oh3fu31tr1 test run........................................... 412 oh3fu31tr2 test run........................................... 413 oh3fu40tr1 testrun............................................ 414 oh3fu40tr2 testrun............................................ 415

oh3fu40tr3 testrun............................................ 416 oh3fu40tr4 testrun............................................ 417 oh3fu40tr5 testrun............................................ 418 oh3fu40tr6 test run........................................... 419 oh3tr1 testrun ................................................... 396 oh3tr10 testrun ................................................. 405

oh3tr2 testrun ................................................... 397 oh3tr3 test run .................................................... 92 oh3tr3 testrun ................................................... 398 oh3tr4 testrun ................................................... 399 oh3tr5 testrun ................................................... 400 oh3tr6 testrun ................................................... 401

oh3tr7 testrun ................................................... 402 oh3tr8 testrun ................................................... 403 oh3tr9 test run .................................................. 404 ohcltr1 test run ................................................. 429 ohcltr2 test run ................................................. 430 ohcltr3 test run ................................................. 431

ohcltr4 test run ................................................. 432 ohcltr5 test run ................................................. 433 OHOOK SUBPROGRAM ................................. 79, 464 OPENFI SUBPROGRAM ....................................... 464

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OPT50 SUBPROGRAM .........................................465 OPT50C SUBPROGRAM .......................................465 OPTIMIZATION SECTION ........................... 154, 303 OPTION SUBPROGRAM ................................ 59, 465

OPTMIN KEYWORD OPTIMIZATION

DEFINITION ..............................................158 OPTTS KEYWORD

OPTIMIZATION DEFINITION ..............................................159

ORD31 SUBPROGRAM ........................................465 Orientation .......................................................... 84 Output

files fu41-fu47 .............................................309 OUTUNIT KEYWORD

DEFINITION ...................................................144

OVRLP SUBPROGRAM ........................................465 P1FREQ SECTION

DEFINITION ...................................................240 P1HESS SECTION

DEFINITION ...................................................237 P2FREQ SECTION

DEFINITION ...................................................240 P2HESS SECTION

DEFINITION ...................................................237 PAGEM KEYWORD..............................................100

TESTRUN EXAMPLE ..... 329, 336, 338, 385, 399 Partition function

electronic........................................................ 34 rotational ..................................................29, 34 vibrational ......................................... 29, 34, 48

PATH SECTION........................................... 181, 307 EXTRAPOLATION KEYWORDS.......................188 INTEGRATOR KEYWORDS .............................186

NES KEYWORDS ...........................................190 PRINT KEYWORDS .........................................189 SSTOR KEYWORDS ........................................190 STEP SIZE KEYWORDS ...................................186 SVRC KEYWORDS..........................................187

PATH SUBPROGRAM ...........................................465

PCFREQA KEYWORD DEFINITION ...................................................286

PCFREQS KEYWORD DEFINITION ...................................................286

PCINFO KEYWORD DEFINITION ...................................................287

PHASE KEYWORD SOLID OPTION

TESTRUN EXAMPLE ......................... 420, 421 PHID SUBPROGRAM ............................................465 PHSINT SUBPROGRAM ........................................465 PIVOT KEYWORD

DEFINITION ...................................................306 PMOI SUBPROGRAM ...........................................465 POLINT SUBPROGRAM .......................................465 POLYAT SUBPROGRAM ............................... 62, 466

POLYRATE DESCRIPTION OF SUBPROGRAMS ................. 441 DIRECTORY STRUCTURE .............................. 310 HIDDEN FILE ................................................. 501

INSTALLATION PROCEDURES ....................... 310 INSTRUCTIONS FOR GENERAL USE ............... 318 MODULE FILES.............................................. 488 PROGRAM STRUCTURE ................................... 59 RUNNING TEST RUNS.................................... 317 TESTING PROCEDURES ................................. 316

potcomp.jc ........................................................ 502 Potential energy surface ............................ 16, 441 POTENTIAL KEYWORD ........................................ 81

DEFINITION...........................................150, 302 UNIT30 OPTION

TESTRUN EXAMPLE406, 407, 408, 409, 410,

414, 415 UNIT40 OPTION

TESTRUN EXAMPLE ................ 416, 417, 418 POTINF KEYWORD ............................................... 71

DEFINITION................................................... 204 PRCORD SUBPROGRAM ..................................... 466

PRDELG KEYWORD DEFINITION................................................... 232

PRDISTMX KEYWORD DEFINITION................................................... 204

PREGPT SUBPROGRAM ...................................... 466 PREP SUBPROGRAM ..................................... 77, 466

PREPJ SUBPROGRAM .................................... 77, 466 PRINT KEYWORD

DEFINITION...........................................159, 239 PRINTSTEP KEYWORD

DEFINITION................................................... 204 PRMEP SUBPROGRAM ........................................ 466

PRMODE KEYWORD DEFINITION................................................... 170

PRNTBT SUBPROGRAM ...................................... 466 PRNTFC SUBPROGRAM ...................................... 466 PROD1 SECTION ................................................. 161 PROD2 SECTION ................................................. 161

PRODFREQ KEYWORD ....................................... 103 DEFINITION................................................... 287

Product force constant matrix .................................... 39 geometry optimization .................................. 37 zero point energy .......................................... 40

PROGRAM FILES ACESPOLY .................................................... 488 EF 489 ENERGETICS ................................................. 489 FROMBLAS.................................................... 489 GIVTST .......................................................... 489

HEADR .......................................................... 489 HOOKS .......................................................... 489 INTBSV1........................................................ 489 INTBSV2........................................................ 489

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INTBSV3 ........................................................489 INTERFACE ....................................................489 IVTSTM ..........................................................490 MAIN .............................................................490

MAIN_VRCMPI ..............................................490 MOPOLY ........................................................490 POLY31 .........................................................490 POLY40 .........................................................490 POLYAG.........................................................490 POLYHL .........................................................490

POLYMQ ........................................................490 POLYRR .........................................................490 POLYSZ..........................................................490 RTPJAC ..........................................................490 VRCTST_MPI .................................................491

PROGRAM SUBPROGRAMS

SETUP ............................................................488 SURF ..............................................................488

PROJCT SUBPROGRAM ................................ 63, 466 PROJECT KEYWORD

DEFINITION ...................................................170 TESTRUN EXAMPLE .......................................386

PROJF SUBPROGRAM ..........................................466 PROJTI SUBPROGRAM ........................................466 PRPART KEYWORD

DEFINITION ...................................................232 PRPATH KEYWORD

DEFINITION ...................................................204

PRSAVEMODE KEYWORD DEFINITION ...................................................205

PRSAVERP KEYWORD .......................................... 71 DEFINITION ...................................................205

PRSQ SUBPROGRAM ...........................................466 PRVIB KEYWORD

DEFINITION ...................................................232 PSAG SUBPROGRAM ...........................................466 PSATP SUBPROGRAM .........................................467 PSATP2 SUBPROGRAM .......................................467 PSATX SUBPROGRAM .........................................467 PSATX2 SUBPROGRAM .......................................467

PTORS SUBPROGRAM .........................................467 PTQVIB SUBPROGRAM .......................................467 PTSEC40 SUBPROGRAM .....................................467 PYC1 SUBPROGRAM ...........................................467 PYC1P SUBPROGRAM .........................................467 PYC2 SUBPROGRAM ...........................................467

PYC2P SUBPROGRAM .........................................467 PYCOEF SUBPROGRAM .......................................468 QFORM SUBPROGRAM .......................................468 QQPOT SUBPROGRAM ........................................468 QQSEMI KEYWORD ........................................90, 91

DEFINITION ...................................................171

RELATED KEYWORDS ...................................165 TESTRUN EXAMPLE .............................. 345, 385

QQWKB KEYWORD.........................................90, 91 DEFINITION ...................................................171

RELATED KEYWORDS................................... 165 TESTRUN EXAMPLE ...................................... 391

QRFAC SUBPROGRAM ........................................ 468 QRSENE SUBPROGRAM ...................................... 468

QRST KEYWORD DEFINITION ................................. 221

QSLVE SUBPROGRAM ........................................ 468 QTQVIB SUBPROGRAM ...................................... 468 QUAD KEYWORD

DEFINITION................................................... 222

QUADFT SUBPROGRAM ..................................... 468 QUADR SUBPROGRAM ....................................... 468 QUADTW SUBPROGRAM .................................... 468 R1FREQ SECTION

DEFINITION................................................... 240 R1HESS SECTION

DEFINITION................................................... 237 R1MPYQ SUBPROGRAM ..................................... 469 R1UPDT SUBPROGRAM ...................................... 469 R2FREQ SECTION

DEFINITION................................................... 240 R2HESS SECTION

DEFINITION................................................... 237 RACES SUBPROGRAM ........................................ 469 RALL31 SUBPROGRAM ...................................... 469 RAN1 SUBPROGRAM .......................................... 469 RANALY SUBPROGRAM ..................................... 469 RANGEIC KEYWORD

DEFINITION................................................... 289 RATE SECTION ...........................................224, 308 Rate section

print keywords............................................. 227 RATE SUBPROGRAM ..............................51, 64, 469 RATOMS SUBPROGRAM ..................................... 469

RBASIS SUBPROGRAM ....................................... 468 RBATH SUBPROGRAM ........................................ 468 RCFREQA KEYWORD

DEFINITION................................................... 288 RCFREQS KEYWORD

DEFINITION................................................... 288

RCINFO KEYWORD DEFINITION................................................... 289

RCNST SUBPROGRAM ........................................ 469 RD40EXTR SUBPROGRAM ................................. 469 RD40GEN SUBPROGRAM ................................... 469 RD40RP SUBPROGRAM ...................................... 469

RDETIL SUBPROGRAM ....................................... 469 RDHESS SUBPROGRAM ...................................... 470 RDIATM SUBPROGRAM ...................................... 469 RDIFFU SUBPROGRAM ....................................... 470 RDLN SUBPROGRAM .......................................... 470 REACFREQ KEYWORD

DEFINITION................................................... 290 REACT SUBPROGRAM .................................. 62, 470 REACT1 SECTION............................................... 161 REACT2 SECTION............................................... 161

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Reactant force constant matrix..................................... 39 geometry optimization .................................. 37 properties ....................................................... 37

zero point energy ........................................... 40 REACTCOM SUBPROGRAM .................................470 Reaction coordinate......................................29, 40

determining the sign of ................................. 65 Reaction path ................................... 29, 40, 41, 50

Euler stabilization method ............................ 42

negative generalized normal mode eigenvalue ................................................................... 50

projected force constant matrix .................... 43 save grid ...................................................43, 63 step sizes ......................................................100

Reaction rate methods keywords.....................226

Reaction rates ..................................................... 48 generalized free energy of activation ........... 48 transmission coefficients............................... 48 transmission probabilities ............................. 48

Boltzmann average ................................... 47 READ5 SUBPROGRAM ................................. 59, 470

READIC SUBPROGRAM .......................................470 READINT SUBPROGRAM .....................................470 READLN SUBPROGRAM ......................................470 REARG1 SUBPROGRAM ......................................470 RECS31 SUBPROGRAM .......................................470 REDGEO SUBPROGRAM ............................... 59, 470

REDMU SUBPROGRAM .......................................471 References

bibliography .................................................512 convention explained ..............................26, 27 footnotes to text ...........................................508

REFOPT SUBPROGRAM .......................................471

RELEC SUBPROGRAM .........................................471 RENERG SUBPROGRAM ......................................471 REORDER KEYWORD

DEFINITION ...................................................205 REPFL SUBPROGRAM ................................ 471, 475 RES1 SUBPROGRAM ...........................................471

RESTART KEYWORD ................................... 66, 106 DEFINITION ...................................................145 TESTRUN EXAMPLE ..... 329, 331, 334, 383, 384

RESTOR SUBPROGRAM ................................ 59, 471 RESTRT SUBPROGRAM .......................................471 RETRY KEYWORD

DEFINITION ...................................................159 Reverse rate constant........................... 31, 50, 103 REVKEXP KEYWORD

DEFINITION ...................................................232 TESTRUN EXAMPLE ......................389, 390, 391

REXTRP SUBPROGRAM .......................................471

REZERO SUBPROGRAM ......................................471 REZERU SUBPROGRAM ......................................471 RFCFAC SUBPROGRAM .......................................471 RFREQ SUBPROGRAM .........................................471

RGEM31 SUBPROGRAM ..................................... 471 RGEN SUBPROGRAM .......................................... 472 RGEN31 SUBPROGRAM ...................................... 472 RGENER SUBPROGRAM...................................... 472

RGEOM SUBPROGRAM ....................................... 472 RGRD SUBPROGRAM .......................................... 472 RGRD31 SUBPROGRAM ..................................... 472 RGSAD SUBPROGRAM........................................ 472 RGSPEC SUBPROGRAM ...................................... 472 RGSZM SUBPROGRAM ....................................... 472

RGTEMP SUBPROGRAM ..................................... 472 RGZMAT SUBPROGRAM ..................................... 472 RHES31 SUBPROGRAM ...................................... 472 RHESS SUBPROGRAM ........................................ 472 RHESSC SUBPROGRAM ...................................... 473 RHFSEC SUBPROGRAM ...................................... 473

RHSS31 SUBPROGRAM ...................................... 473 RICOPT SUBPROGRAM ....................................... 473 RLCT SUBPROGRAM .......................................... 473 RLINE SUBPROGRAM ......................................... 473 RLOWFR SUBPROGRAM ..................................... 473 RMUVT SUBPROGRAM ....................................... 473

RODS KEYWORD DEFINITION................................................... 205

ROPT SUBPROGRAM .......................................... 473 ROPT31 SUBPROGRAM ...................................... 473 ROPTOP SUBPROGRAM ...................................... 473 rotate utility program ....................................... 497

RPART SUBPROGRAM ........................................ 473 RPARTI SUBPROGRAM ....................................... 473 RPATH SUBPROGRAM ........................................ 473 RPH31 SUBPROGRAM ........................................ 473 RPH40 SUBPROGRAM ........................................ 474 RPHAIT SUBPROGRAM ....................................... 474

RPHB SUBPROGRAM .......................................... 474 RPHDXN SUBPROGRAM ..................................... 474 RPHEXP SUBPROGRAM ...................................... 474 RPHFIT SUBPROGRAM ....................................... 474 RPHFT2 SUBPROGRAM ...................................... 474 RPHFT3 SUBPROGRAM ...................................... 474

RPHG1 SUBPROGRAM ........................................ 474 RPHG2 SUBPROGRAM ........................................ 474 RPHG5 SUBPROGRAM ........................................ 474 RPHINT SUBPROGRAM ....................................... 474 RPHMEF SUBPROGRAM ..................................... 474 RPHNWT SUBPROGRAM ..................................... 475

RPHRD1 SUBPROGRAM ...................................... 475 RPHRD2 SUBPROGRAM ...................................... 475 RPHSET SUBPROGRAM ...................................... 475 RPHTRF SUBPROGRAM ...................................... 475 RPHTRX SUBPROGRAM ...................................... 475 RPHWRT SUBPROGRAM ..................................... 475

RPIVOT SUBPROGRAM ....................................... 475 RPL KEYWORD................................................... 106 RPM KEYWORD

DEFINITION ................................................... 206

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RPNT31 SUBPROGRAM .......................................475 RPOTET SUBPROGRAM .......................................475 RPOTGE SUBPROGRAM ......................................475 RPRMEP SUBPROGRAM ......................................475

RPRVIB SUBPROGRAM .......................................476 RPSEC40 SUBPROGRAM .....................................476 RP-VTST rate constants .................................... 15 RQCOM SUBPROGRAM .......................................476 RQRST SUBPROGRAM .........................................476 RQUAD SUBPROGRAM .......................................476

RRANGE SUBPROGRAM ......................................476 RRATE SUBPROGRAM ........................................476 RRPM SUBPROGRAM ..........................................476 RRSTRT SUBPROGRAM .......................................476 RSCT SUBPROGRAM ...........................................476 RSECND SUBPROGRAM ......................................476

RSFRST SUBPROGRAM .......................................476 RSP SUBPROGRAM .............................................476 RSPDRV SUBPROGRAM ......................................476 RSPECL SUBPROGRAM .......................................477 RSPP SUBPROGRAM ............................................477 RSSTOP SUBPROGRAM .......................................477

RST SUBPROGRAM .............................................477 RSTAT SUBPROGRAM .........................................477 RSTATE SUBPROGRAM .......................................477 RSVRC SUBPROGRAM ........................................477 RTEMP SUBPROGRAM ........................................477 RTITLE SUBPROGRAM ........................................477

RTOR SUBPROGRAM ..........................................477 RTOROPT SUBPROGRAM ....................................477 RTPJAC SUBPROGRAM .......................................477 RTUNNL SUBPROGRAM ......................................477 RUNM31 SUBPROGRAM .....................................477 RVAR6 SUBPROGRAM ........................................478

RVARY SUBPROGRAM ........................................478 RVPERT SUBPROGRAM .......................................478 RVRANG SUBPROGRAM .....................................478 RVRCOPT SUBPROGRAM ....................................478 RWKB SUBPROGRAM .........................................478 RWORD SUBPROGRAM .......................................478

RZVAR SUBPROGRAM ........................................478 SADDLE KEYWORD .............................................. 41

DEFINITION ...................................................206 SADDLE SUBPROGRAM ............................... 41, 478 SADENG SUBPROGRAM ......................................478 SADFREQ KEYWORD

DEFINITION ...................................................290 SADSEC40 SUBPROGRAM ..................................479 Sample test runs................................................326 Save grid .......................................................43, 63 SAVEXRP SUBPROGRAM ....................................479 SCALE KEYWORD

DEFINITION ...................................................160 SCALEMASS KEYWORD........................................ 63

DEFINITION ...................................................206 TESTRUN EXAMPLE .......................................332

SCLPT KEYWORD DEFINITION................................................... 207

Scripts comp_pot.jc ................................................. 502

comp_src.jc ................................................. 503 link_exe.jc ................................................... 504 potcomp.jc ................................................... 502

SCT KEYWORD DEFINITION................................................... 222 TESTRUN EXAMPLE ..............................329, 338

SCTOPT KEYWORD DEFINITION................................................... 223 LAGRANGE OPTION ...................................... 101

TESTRUN EXAMPLE .........................336, 342 TESTRUN EXAMPLE ................................. 332

TESTRUN EXAMPLE

SPLINE OPTION ........................................ 333 SDEB1 KEYWORD

DEFINITION ................................................... 207 SDEB2 KEYWORD

DEFINITION ................................................... 207 SDSTART KEYWORD

DEFINITION................................................... 160 SECCEN SUBPROGRAM ...................................... 479 SECCEP SUBPROGRAM ....................................... 479 Second derivatives

central differences ....................................... 101 numerical ....................................................... 98

numerical fourth order polynomial .............. 98 quadratic fit ................................................... 98

SECOND SECTION .............................................. 151 SECOND SECTION KEYWORDS

POLYRATE ..................................................... 151 SENOUT SUBPROGRAM ...................................... 479

SETANH SUBPROGRAM ...................................... 479 SETLGS SUBPROGRAM ....................................... 479 SETUP SUBPROGRAM .............................69, 74, 479 SETVAR SUBPROGRAM ...................................... 479 SEX1 KEYWORD

DEFINITION................................................... 239

SFIRST KEYWORD .............................................. 100 DEFINITION................................................... 208 TESTRUN EXAMPLE ..............................342, 396

SGND3V SUBPROGRAM ..................................... 479 SHFTSAD SUBPROGRAM .................................... 479 SIGMAF KEYWORD

DEFINITION...........................................232, 308 SIGMAR KEYWORD

DEFINITION................................................... 233 SIGN KEYWORD ................................................... 65

DEFINITION................................................... 208 SIGS SUBPROGRAM ............................................ 479

SIMPSN SUBPROGRAM ....................................... 480 SINE SUBPROGRAM ........................................... 480 Small-curvature Tunneling.......................... 15, 35 SNHCSH SUBPROGRAM ...................................... 480

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SORT31 SUBPROGRAM .......................................480 SORTG SUBPROGRAM ........................................480 SPECIES KEYWORD

DEFINITION ...................................................171

SPECSTOP KEYWORD DEFINITION ...................................................209

SPL1B1 SUBPROGRAM .......................................480 SPL1B2 SUBPROGRAM .......................................480 SPL1D1 SUBPROGRAM .......................................480 SPL31 SUBPROGRAM .........................................480

SPLM31 SUBPROGRAM ......................................481 SPLNB SUBPROGRAM .........................................480 SPLNF SUBPROGRAM .........................................480 SPLNM SUBPROGRAM ........................................480 SPLNMF SUBPROGRAM ......................................481 SPLNV SUBPROGRAM .........................................481

SPLRMI SUBPROGRAM .......................................481 SPLSPV SUBPROGRAM .......................................481 SPLV31 SUBPROGRAM .......................................481 SPRNT KEYWORD

DEFINITION ...................................................210 SRANGE KEYWORD

DEFINITION ...................................................210 TESTRUN EXAMPLE ......................392, 394, 395

SSAVE SUBPROGRAM .........................................481 SSPECIAL KEYWORD

DEFINITION ...................................................210 TESTRUN EXAMPLE .......................................391

SSPECPR KEYWORD DEFINITION ...................................................211

SS-QRRK............................................... 2, 12, 500 SSTEP KEYWORD..................................... 42, 62, 99

DEFINITION ...................................................211 TESTRUN EXAMPLE ......................334, 337, 385

SSTOR ......................................... 90, 172, 190, 211 SSX SUBPROGRAM .............................................481 START SECTION..................................................161 STAT31 SUBPROGRAM .......................................481 STATE KEYWORD

ADIAB OPTION

TESTRUN EXAMPLE ..................................399 DEFINITION ...................................................233 DIAB OPTION

TESTRUN EXAMPLE ..................................400 STATEOPT KEYWORD

DEFINITION ...................................................234

STATUS KEYWORD DEFINITION ...................................................171

STAUV SUBPROGRAM ........................................481 STLGSJ SUBPROGRAM ........................................482 STOR SUBPROGRAM ...........................................482 STPTOL KEYWORD

DEFINITION ....................................................160 STVARJ SUBPROGRAM .......................................482 SUPERMOL KEYWORD

DEFINITION ...................................................145

SURF SUBPROGRAM ................. 69, 70, 72, 74, 482 SVBCMP SUBPROGRAM ..................................... 482 SVBKSB SUBPROGRAM ...................................... 482 SVRC KEYWORD

DEFINITION................................................... 307 SYMMETRY KEYWORD

DEFINITION................................................... 211 TESTRUN EXAMPLE ..............................387, 388

TABLE SUBPROGRAM ........................................ 482 TAUV SUBPROGRAM .......................................... 482

TEMP KEYWORD DEFINITION................................................... 235 RELATED KEYWORDS...........................228, 229 TESTRUN EXAMPLE ............. 329, 338, 389, 390

THETA2 SUBPROGRAM ...................................... 482 THETA3 SUBPROGRAM ...................................... 482

TITLE KEYWORD DEFINITION................................................... 146

TITLE SUBPROGRAM .......................................... 482 TOR KEYWORD

DEFINITION................................................... 172 TESTRUN EXAMPLE ..................... 383, 384, 422

TOROPT KEYWORD DEFINITION................................................... 173

TP SUBPROGRAM ............................................... 482 TPCDSC SUBPROGRAM ...................................... 483 TQL2 SUBPROGRAM .......................................... 483 TQLRAT SUBPROGRAM ...................................... 483

TRANFC SUBPROGRAM ...................................... 483 TRANG SUBPROGRAM ....................................... 483 TRANLF SUBPROGRAM ...................................... 483 TRANS SUBPROGRAM ........................................ 483 TRANS2 SUBPROGRAM ...................................... 483 TRANSF SUBPROGRAM ...................................... 483

Transmission coefficients......... 31, 35, 36, 48, 49 TRBAK3 SUBPROGRAM ..................................... 483 TRED3 SUBPROGRAM ........................................ 483 TREPT SUBPROGRAM ......................................... 483 TRLFRP SUBPROGRAM ....................................... 483 TSC SUBPROGRAM ............................................. 484

TSFREQ SECTION DEFINITION................................................... 240

TSGCOMP KEYWORD DEFINITION ................................................... 156

TSHESS SECTION DEFINITION................................................... 237

TSHREC KEYWORD DEFINITION................................................... 157

TSOUT SUBPROGRAM .................................. 51, 484 TSPSI SUBPROGRAM .......................................... 484 TSRATE SUBPROGRAM ................................ 51, 484 TST

TESTRUN EXAMPLE ...................................... 334 TST KEYWORD

DEFINITION................................................... 235 TESTRUN EXAMPLE ...................................... 382

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TUNNEL SECTION ...............................................213 Tunneling

canonical optimized multidimensional ........ 52 interpolation of effective reduced mass .....101

microcanonical optimized multidimensional ................................................................... 52

TURNPT SUBPROGRAM ......................................484 UNITMI KEYWORD

DEFINITION ...................................................290 TESTRUN EXAMPLE .......................................393

UNITS KEYWORD DEFINITION ...................................................239

UPCAS SUBPROGRAM .........................................484 UPCSE SUBPROGRAM .........................................484 UPDHR SUBPROGRAM ........................................484 UPDMI SUBPROGRAM .........................................484

US KEYWORD DEFINITION ...................................................235 TESTRUN EXAMPLE .............................. 389, 390

Utility routines chain ............................................................... 73 coord............................................................... 72

VALVAG SUBPROGRAM .....................................484 VANHAR KEYWORD

DEFINITION ...................................................178 TESTRUN EXAMPLE ..... 345, 383, 384, 385, 391

VARIABLE KEYWORD .......................................... 91 Variable Reaction Coordinate and Multifaceted

Dividing Surface algorithm ............... 125, 131 VECCON SUBPROGRAM ......................................485 VECMAG SUBPROGRAM .....................................485 VIB KEYWORD

DEFINITION ...................................................179 VICLCG SUBPROGRAM .......................................485

VIVT SUBPROGRAM ...........................................485 VPART SUBPROGRAM ........................................485 VPARTI SUBPROGRAM .......................................485 VPFEXP KEYWORD

DEFINITION ...................................................235 TESTRUN EXAMPLE .............................. 332, 336

VRANGE KEYWORD ............................................. 91 DEFINITION ...................................................180

VRC ....................................................................125 VRC KEYWORD ..................................... 44, 59, 299

DEFINITION ...................................................300 VRCNEJ SUBPROGRAM .......................................485

VRCOPT KEYWORD DEFINITION ...................................................300

VRCTST SUBPROGRAM .......................................485 VSCALE KEYWORD

DEFINITION ...................................................212 VSPLI2 SUBPROGRAM ........................................485

VSPLIN SUBPROGRAM ........................................485 VTMUSN SUBPROGRAM .....................................485 VTST-IOC ......................................................... 56 VTST-ISPE .......................................................106

WELLP SECTION................................................. 161 WELLR SECTION ................................................ 161 WIGNER KEYWORD

DEFINITION................................................... 223

Wigner tunneling ......................................... 40, 48 WKB KEYWORD ....................................... 90, 91, 92

DEFINITION................................................... 180 TESTRUN EXAMPLE ...................................... 398

WKB METHOD based on true potential .................................. 92

PRIMITATIVE .................................................. 91 UNIFORM ........................................................ 91

WKBENE SUBPROGRAM ..................................... 486 WKBPOT SUBPROGRAM ..................................... 486 WKBVIB SUBPROGRAM ..................................... 486 WRITE62 KEYWORD

DEFINITION................................................... 146 WRITEFU30 KEYWORD

DEFINITION................................................... 146 WRITEFU31 KEYWORD

DEFINITION................................................... 147 WRTHOK SUBPROGRAM .................................... 486

WRTWEL SUBPROGRAM .................................... 486 WTITLE SUBPROGRAM ...................................... 485 WVAR6 SUBPROGRAM ....................................... 486 XDOTP SUBPROGRAM ........................................ 486 XERBLA SUBPROGRAM...................................... 486 XPROD SUBPROGRAM........................................ 486

YDER24 SUBPROGRAM ...................................... 486 YDERV2 SUBPROGRAM ..................................... 486 YNEWT SUBPROGRAM ....................................... 486 YSECEN SUBPROGRAM ...................................... 487 YSECEP SUBPROGRAM ...................................... 487 YTRANS SUBPROGRAM...................................... 487

ZCT KEYWORD DEFINITION................................................... 223 TESTRUN EXAMPLE ....329, 333, 334, 335, 338,

340, 422, 424, 425 Zero of energy .................................................... 68 Zero-curvature Tunneling ........................... 15, 35

ZEROPT SUBPROGRAM ...................................... 487 ZERP SUBPROGRAM ........................................... 487 ZIGAMA SUBPROGRAM...................................... 487 ZOC3P SUBPROGRAM ........................................ 487 ZOCAST SUBPROGRAM ...................................... 487 ZOCFRE SUBPROGRAM ...................................... 487

ZOCPAR SUBPROGRAM ...................................... 487 ZOCPRN SUBPROGRAM ...................................... 487 ZOCUPD SUBPROGRAM...................................... 487 ZOCVCL SUBPROGRAM...................................... 487 ZRIDDR SUBPROGRAM ...................................... 488 ZROUT SUBPROGRAM ........................................ 488

ZRPTE SUBPROGRAM ......................................... 488 ZSPMEP SUBPROGRAM ...................................... 488 µOMT ................................................................... 52 µVT ...................................................................... 28

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